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Skip Towne
06-16-2005, 03:26 PM
My daughter's 94 Grand Am 4 cylinder car is acting up. You can be driving along at 55 mph and feel it falter. When you give it gas, it catches and starts accelerating again and a cloud of black smoke comes out the exhaust. It also does this at slower speeds in town. The tailpipe is coated with a black soot. She says it runs normal out on the interstate at 70 mph. Any ideas what is wrong with it?

Brock
06-16-2005, 03:34 PM
Prolly time for a fuel pump/regulator.

Soupnazi
06-16-2005, 03:35 PM
Is that the old quad-4? Black soot usually indicates it being rich, could be due to a number of things. My bet would probably be a clogged fuel injector or a bad MAF sensor.

Have you pulled the plugs yet?

Dr. Facebook Fever
06-16-2005, 03:37 PM
I'd take it to a mechanic. I hear they handle these things every day.

Phobia
06-16-2005, 03:51 PM
I refuse to believe there is a Pontiac product more than 10 years old and not more than 30 still driving the roads. You should kill it immediately.

Skip Towne
06-16-2005, 03:56 PM
It's fuel injected. What causes that black soot?

Calcountry
06-16-2005, 03:59 PM
Damn funny chit Skip, I have an 87 Ford Econoline van that does similar thing, only when I turn right and when I go up a grade, not many where I live. It dies when driving up into my parking lot. It also has black soot by the tail pipe.

You helped me buddy. Thanks.

AustinChief
06-16-2005, 04:04 PM
also could be an intake leak or simply the O2 sensor... or the MAP sensor.. or pvc or retarded engine timing .. but it definitely is running rich, and I'm sure the plugs will need to be changed out after you fix the main problem.

We really need more info... like how does it idle?

For my money.. I would guesss it is the M.A.P sensor.

--Kyle

AustinChief
06-16-2005, 04:09 PM
Any check engine lights on?

Soupnazi
06-16-2005, 04:10 PM
It's fuel injected. What causes that black soot?

Generally speaking, way too much fuel. 1994 would probably have been an OBD II car, which means it could be a bad fuel injector, bad O2 sensor, bad mass air flow sensor, bad fuel pressure regulator, etc. The best way to get a clue is to try checking diagnostic codes.

AustinChief
06-16-2005, 04:11 PM
Also.. if it appears to be the MAP sensor... check the voltage to it and the lines for cracks BEFORE replacing the sensor itself.

Dave Lane
06-16-2005, 04:11 PM
My daughter's 94


Damn Skip I knew you were old but christ almighty!!!

Dave

AustinChief
06-16-2005, 04:19 PM
Generally speaking, way too much fuel. 1994 would probably have been an OBD II car, which means it could be a bad fuel injector, bad O2 sensor, bad mass air flow sensor, bad fuel pressure regulator, etc. The best way to get a clue is to try checking diagnostic codes.

I stole this from a mechanic website...

To determine which you have, look on the fan shroud for the VECI label to see if it has on the label, something like "OBD2 certified". If it says that, you'll need a scan tool to pull the codes.

If it doesn't then you can pull the codes youself by grounding the proper pin on the ALDL connector & watching & counting the CEL on the dash blink the stored codes.

Apparently '94 was when they switched from OBD1 to OBD2, so quite a few vehicles that year were still OBD1. It is worth checking.

--Kyle

Skip Towne
06-16-2005, 04:24 PM
Any check engine lights on?
Check engine light comes and goes. Anyone know how to check those codes? I know how to do it on my Astrovan but not a Pontiac.

Dartgod
06-16-2005, 04:26 PM
We really need more info... like how does it idle?
Oooo, good point. she could have a bad idler arm.

Saggysack
06-16-2005, 04:29 PM
Your problem is that it is a Pontiac Grand Am.

After high school I took a job with a local Pontiac dealership. We always had atleast 5 new Grand Am engines on stock.

Take the car to the lake, pour gasoline over the engine and light it up. Come home, report the damn thing stolen. In a week you will get a call from LE telling you that a park ranger has found your car. Unfortunately it has springs for seats and won't start.

AustinChief
06-16-2005, 04:30 PM
Check engine light comes and goes. Anyone know how to check those codes? I know how to do it on my Astrovan but not a Pontiac.

IF it is OBD1 AND it is OBD1 with a 12pin connector (Gm got screwy and had a 16pin ODB2 style connector with OBD1 computers underneath for awhile in late 94 and 95).. anyway.. IF those are both true than you can just jump pins A and B (a paperclip will do it) and then read the blinks from the check engine light.

Advice taken at your own risk...

--Kyle

Skip Towne
06-16-2005, 04:34 PM
Also.. if it appears to be the MAP sensor... check the voltage to it and the lines for cracks BEFORE replacing the sensor itself.
Does that site mention where the MAP sensor is located and what the voltage should be?

AustinChief
06-16-2005, 04:35 PM
You can also just buy a scanner off ebay... one of these www.autoxray.com costs between $100-$175 and will read all OBD1 and 2 systems. Handy to have if you can do alot of your own car work.

--Kyle

VEHICLE COVERAGE
GM '82 - Current Year (12 & 16 pin ALDL and OBD-II)
Ford '83 - Current Year (EEC IV and OBD-II)
Chrysler '83 - Current Year (SCI and OBD-II)
Jeep '91 - Current Year (SCI and OBD-II)
Toyota '96 - Current Year (OBD-II)
Honda '96 - Current Year (OBD-II)
NISSAN '96 - Current Year (OBD-II)
All other Asian and European '96 - Current Year (OBD-II)

AustinChief
06-16-2005, 04:37 PM
Does that site mention where the MAP sensor is located and what the voltage should be?

nope.. can't find that anywhere... I imagine the best place to find that info is a Chilton's or Haynes manual. Or you can always call a dealer shop and get them to fax you a diagram if they are nice... or hell ask KCMizzou he probably knows.. if he can't find it's location under the hood at least he can tell you exactly what it looks like.

--Kyle

AustinChief
06-16-2005, 04:40 PM
Last piece of advice... some auto parts stores will check this for you... Find out what you have (especially important if it is 12 or 16 pin) and then call around and see if one will do it. It is amazing what some of the guys at parts stores know and how much they will help out if they aren't busy inside.

--Kyle

Skip Towne
06-16-2005, 05:18 PM
I wish Brandon would come on here and tell me what he knows about it.

chiefkdawg
06-16-2005, 06:31 PM
B4 you do any of that, try taking out the spark plugs and if any of them are black and moist looking you might just have a dead cylinder, in which case you just replace wires and plugs , possibly cap and rotor. I had a 2000 neon that did that and all it was was the wires.

C-Mac
06-16-2005, 06:52 PM
Oooo, good point. she could have a bad idler arm.

ROFL

Skip Towne
06-16-2005, 07:11 PM
B4 you do any of that, try taking out the spark plugs and if any of them are black and moist looking you might just have a dead cylinder, in which case you just replace wires and plugs , possibly cap and rotor. I had a 2000 neon that did that and all it was was the wires.
I'm sure it isn't a dead cylinder. After the hesitation and the black smoke it runs like a striped assed ape. It would still have a dead miss if it were a dead cylinder.

C-Mac
06-16-2005, 07:50 PM
I assume it idles OK, so if its only doing this during a load then its either not getting enough oxygen or too much fuel is dumping in. This can be caused by things such as a bad plug, a bad plugwire, a fuel injector, the timing advance is stuck and maybe an OS or MAP.
There, that narrows you down :D

Skip Towne
06-16-2005, 07:56 PM
I assume it idles OK, so if its only doing this during a load then its either not getting enough oxygen or too much fuel is dumping in. This can be caused by things such as a bad plug, a bad plugwire, a fuel injector, the timing advance is stuck and maybe an OS or MAP.
There, that narrows you down :D
Yeah, Craig, it idles just fine. (So I don't need an idler arm, Dartgod you dumbass). I'm going to call Terry in the AM.

C-Mac
06-16-2005, 08:31 PM
Yeah, Craig, it idles just fine. (So I don't need an idler arm, Dartgod you dumbass). I'm going to call Terry in the AM.

I had just left a message tonite with my sister on getting together at the Arrowhead party on Saturday, so if she calls me back tonite and Terry's home, I ask him for you.
:D

Skip Towne
06-16-2005, 08:35 PM
I had just left a message tonite with my sister on getting together at the Arrowhead party on Saturday, so if she calls me back tonite and Terry's home, I ask him for you.
:D
That would be great. You could just email him this thread. It would save us plowing the same ground again.

papasmurf
06-16-2005, 08:54 PM
I had a 92 Gran am thet did the same thing. the computer need to be recalibrated .

Skip Towne
06-16-2005, 09:02 PM
I had a 92 Gran am thet did the same thing. the computer need to be recalibrated .
How did you find that out?

C-Mac
06-16-2005, 09:21 PM
OK Talked to Terry, he thinks its......
1. MAP\MAP wiring\Vacuum Leak to Map
Its located on throttle in the front on a Quad 4.

2. OS

He also said AutoZone will read your code for free.
If you want to reset your computer, take the positive post of your battery and touch the neg side with it.

Bwana
06-16-2005, 10:11 PM
Damn Skip, Without my manuals, I don't kow what to tell you on this one bud. I am stuck here in Spokane for another fuggen week too.

Skip Towne
06-17-2005, 05:27 AM
Thanks C-Mac and Bwana. I think I have enough info now. I'm going to take it to Autozone and let them tell me what I need. I sure appreciate the help.

JOhn
06-17-2005, 05:51 AM
I have a 92 Dodge caravan, I swore I wouldn't buy another one but I did :banghead: , that I drive about 250 miles a day with. it is a 3.3 liter 6cyl with about 120,000 on it. I have already replaced the Ignition coil pack, fuel filter and battery when I bought it. But it still has a problem.

When your cruising along and you depress the accelerator it will down shift and then start hesitating badly, and will backfire. If you ease up on the gas a little, it will smooth out and accelerate just fine. It also will occasionally do this if you go from a standstill and punch the gas, it then will hesitate and backfire as it get ready to shift to the next gear. Again if you ease back on the gas it will smooth out fine.

I thought it might have been the coil or fuel filter, but was no help changing them. It idles just fine, no missing or rough idle at all. If fact runs terrific other than what i indicated. Any ideas?

Oh on one or two occasions when it has done this the check engine light has come on, but that was the only times, 99% of the other time it doesn't.

stumppy
06-17-2005, 06:45 AM
Skip, I'm not as familiar with Pontiacs as I am Chrysler products but I'll bet C-mac/Terry is right. My first thought was an O2 sensor.

JOhn JOhn JOhn, You started throwing parts at it before you diagnosed the problem ?:shake:

When you say it backfires do you mean like a big Kapow coming out of the tailpipe ? Or do you mean some popping / backfireing coming from the engine compartment ? If it's popping under the hood you more than likely have a bad plug wire. Possibly a bad spark plug. Try starting it up in your driveway. Foot on brake, put it in D, press on accelerator pedal . Hold down on the brake pedal pretty hard and accel. until it almost has enough power to move the van. Keep the engine rev up like that for 10 to 15 seconds. Maybe let of and rev it up again. Listen for the "backfire". If the engine starts missing and you also hear the popping noise under the hood it's a plug wire. If it starts missing and you hear no pop noise it's a plug.
And the Check Eng. Light is more than likely an 'Engine Cylinder Missfire' code. Probably caused by a bad plug or wire.


NOW, would anyone like to come work on the air ride suspension on my lincoln ?

JOhn
06-17-2005, 06:55 AM
Cool, I do have a set of plugs to put in it, and will get some wires. I'm sure they havn't been changed in awhile anyway.

As for the Fuel filter, good preventive maintenance, as it was the original one. As for the coil pack, I've had the go out at 120,000 to 150,000 on all 3 caravans I've had, just being proactive. :rolleyes:


Oh and it is the small kinda backfire, not the big earth shaking tail pipe kind.

Radar Chief
06-17-2005, 08:12 AM
It's fuel injected. What causes that black soot?

Running to rich, the cylinder is getting too much fuel into the air/fuel mixture and the unburned fuel is getting spit out the back as that black soot.
You need to cure this soon, or it’ll clog your catalytic converter and run into more $$$.
Could be any number of things causing it, leaking injector, bad MAF or MAP sensor, O2 sensor or temp sensor.
You could go to your local parts store and get a reader that you plug into the cars engine management system and read the default codes.
That or take it to a mechanic to do the same thing.
For a small fee, comparatively, they’ll read the default codes and tell you what they are. Then you can replace parts on your own, and if you can get it done without visiting the mechanic too many times this would be cheaper than buying a reader.

Radar Chief
06-17-2005, 08:16 AM
Oooo, good point. she could have a bad idler arm.

Probably a bad Isosolator. ;)

stumppy
06-17-2005, 08:18 AM
When you replace the plugs and wires be sure and use Champion plugs and if you don't want to pay the bucks for OEM wires(which I HIGHLY recommend) don't buy just any brand of wires. Pay the extra money and buy top quality wires. For some reason most chrysler products have problems with the ignition system if you don't use OEM parts or top quality after market parts. You can install the cheaper parts and it will probably run alright for awhile but the lower quality stuffs seems to start giving you problems a lot sooner than the good stuff.

Coil packs ? On all 3 vehicles ? That sounds way out of character for those vehicles. I spent 6 to 7 years in Chrysler service departments and I honestly can't recall ever having to replace a coil pack on any of the mini-vans. Oh well, you never know.

A couple of tips that might help extend the life of your mini van. Or at least keep your repair bills down.
Change the air filter and pcv valve at least ever 20,000 miles. When you change them get an old toothbrush and some carb cleaner, open the throttle body blade, spray carb cleaner generously inside t-body. Scrub it real good, all over the inside and both sides of the T-body blade. Always carry an extra serpentine belt tensioner and belt with you.(along with the tools to change them) Never run your gas tank down below 1/4 tank.(Fuel pump runs alot cooler) Change Trans. fluid and filter every 30,000 miles(if it is the overdrive tranny) If it has the regular 3 speed you can get by with 50,000 mile service.
The 3.3 litre engine is just about bullet proof and if it has the 3 speed tranny you've got a drive train that will run forever.

And always carry a big stick with you. Those mini-vans are pussy gettin mother fuggers and you'll need something to fight the girls off with.:D

Radar Chief
06-17-2005, 08:20 AM
Thanks C-Mac and Bwana. I think I have enough info now. I'm going to take it to Autozone and let them tell me what I need. I sure appreciate the help.

Ah, never mind. I see they’ve already got ya pointed in the right direction.
And I agree with Austin, you’ll need new plugs when this is done. They’re more than likely fouled with all that soot.

Lzen
06-17-2005, 08:27 AM
Probably a bad Isosolator. ;)

Don't forget to check the blinker fluid. ;)

papasmurf
06-17-2005, 08:43 AM
How did you find that out?

Service tech told me

JOhn
06-17-2005, 09:05 AM
Coil packs ? On all 3 vehicles ? That sounds way out of character for those vehicles. I spent 6 to 7 years in Chrysler service departments and I honestly can't recall ever having to replace a coil pack on any of the mini-vans. Oh well, you never know.

The 3.3 litre engine is just about bullet proof and if it has the 3 speed tranny you've got a drive train that will run forever.

And always carry a big stick with you. Those mini-vans are pussy gettin mother fuggers and you'll need something to fight the girls off with.:D


Yea I hate were they placed the coil pack, it tends to get way to hot were it is. In fact I have learned to move it to the firewall, which seems to keep it a lot cooler.

I hope it is a good tranny, as I know the Caravans are notorious for losing the trans at 130,000 or so.

The wife is pretty good at making sure I won't need a big stick, she damn mean and possessive. Besides it's nothing more than a work vehicle.

ExtremeChief
06-17-2005, 10:23 AM
My Grand Am did that and I had to replace the kenutin modulator to stop the hesitation and the muffler bearings to stop the black soot.

Hope that helps.

C-Mac
06-17-2005, 10:24 AM
Thanks C-Mac and Bwana. I think I have enough info now. I'm going to take it to Autozone and let them tell me what I need. I sure appreciate the help.

Let us know what you find out.

Skip Towne
06-17-2005, 10:28 AM
Let us know what you find out.
I sure will.

Rukdafaidas
06-17-2005, 10:42 AM
My Grand Am did that and I had to replace the kenutin modulator to stop the hesitation and the muffler bearings to stop the black soot.

Hope that helps.
Yeah, it's all ball bearings these days.
I recommend some 3-in-1 oil and some gauze pads.

JOhn
06-17-2005, 09:33 PM
When you replace the plugs and wires be sure and use Champion plugs and if you don't want to pay the bucks for OEM wires(which I HIGHLY recommend) don't buy just any brand of wires. Pay the extra money and buy top quality wires. For some reason most chrysler products have problems with the ignition system if you don't use OEM parts or top quality after market parts. You can install the cheaper parts and it will probably run alright for awhile but the lower quality stuffs seems to start giving you problems a lot sooner than the good stuff.



Nope, still acting up. replaced the Wires & Plugs with OEM.

Still cuts out & runs real rough when you idle it up high, or are driving and punch the gas, Any other ideas?

Skip Towne
06-17-2005, 09:39 PM
Nope, still acting up. replaced the Wires & Plugs with OEM.

Still cuts out & runs real rough when you idle it up high, or are driving and punch the gas, Any other ideas?
Is it injected? If so, stick your finger in the tailpipe and check for dry black soot.

Skip Towne
06-17-2005, 09:41 PM
Could also be distributor cap or rotor.

JOhn
06-17-2005, 09:42 PM
Is it injected? If so, stick your finger in the tailpipe and check for dry black soot.
Nope, not any signs of that.

JOhn
06-17-2005, 09:42 PM
Could also be distributor cap or rotor.
Not applicable to this engine, has a coil pack which I have allready changed.

Skip Towne
06-17-2005, 09:45 PM
Not applicable to this engine, has a coil pack which I have allready changed.
Coil pack? Smells like a Dodge. You're on your own.

JOhn
06-17-2005, 09:46 PM
Coil pack? Smells like a Dodge. You're on your own.
ROFL

Yup, only reason I own one is for work. It was cheap and fitted my needs.

All my other real vehicles are Fords or Toyota's. :thumb:

stumppy
06-17-2005, 11:12 PM
Nope, still acting up. replaced the Wires & Plugs with OEM.

Still cuts out & runs real rough when you idle it up high, or are driving and punch the gas, Any other ideas?

I'm not a mechanic in real life, although I do play one on TV.
:D





Seriously though, I made a rookie mistake when it comes to diagnosing a driveability problem. I went mostly by your description of the problem instead of asking the questions I need answered in order to figure out whats wrong. Sorry man.(It still doesn't mean I'll get it right but I used to be pretty damn good driveabilty diagnostics)
When you say 'idle it up high' do you mean just sitting still, in park or neutral and reving the engine up ? Or does it have to be in gear and under a load like you described in your first post ?

I've got to leave shortly but when I get a chance tonight or in the A.M. I'll PM you with a few questions and see if I can figure it out for you.

JOhn
06-17-2005, 11:19 PM
I'm not a mechanic in real life, although I do play one on TV.
:D





Seriously though, I made a rookie mistake when it comes to diagnosing a driveability problem. I went mostly by your description of the problem instead of asking the questions I need answered in order to figure out whats wrong. Sorry man.(It still doesn't mean I'll get it right but I used to be pretty damn good driveabilty diagnostics)
When you say 'idle it up high' do you mean just sitting still, in park or neutral and reving the engine up ? Or does it have to be in gear and under a load like you described in your first post ?

I've got to leave shortly but when I get a chance tonight or in the A.M. I'll PM you with a few questions and see if I can figure it out for you.

In park if I rev it up it will start cutting out and running real rough.

Driving it still does as I described earlier

Skip Towne
06-17-2005, 11:25 PM
ROFL

Yup, only reason I own one is for work. It was cheap and fitted my needs.

All my other real vehicles are Fords or Toyota's. :thumb:
Look around for a Chevy Astrovan. The older ones are really cheap but will run forever. Mine has 320,000 miles on it. My buddy just bought one for $500 and he drives it every day doing satellite installs. They are easy to work on compared to most vans. Plus I know a lot about them and can help you with any problems you might have. Coca Cola has a nationwide fleet of them. They are red with Coca Cola logos on them.

JOhn
06-17-2005, 11:30 PM
Look around for a Chevy Astrovan. The older ones are really cheap but will run forever. Mine has 320,000 miles on it. My buddy just bought one for $500 and he drives it every day doing satellite installs. They are easy to work on compared to most vans. Plus I know a lot about them and can help you with any problems you might have. Coca Cola has a nationwide fleet of them. They are red with Coca Cola logos on them.

Must be a regional thing, seriously you find many more Caravans around here for sale.

Besides for the most part I'm already very familiar with repair work on them, this is the first time I've been stumped with a problem on them that I couldn't figure out. :shrug:

CrazyHorse
06-18-2005, 05:23 AM
Does anyone else here think it could be the exhaust sensor?

Fried Meat Ball!
06-18-2005, 05:38 AM
So Skip... your daughter has soot in her tailpipe?

ROFL

JOhn
06-18-2005, 01:36 PM
Does anyone else here think it could be the exhaust sensor?
:spock:

JOhn
06-18-2005, 01:36 PM
So Skip... your daughter has soot in her tailpipe?

ROFL
:LOL: ROFL

Baby Lee
06-18-2005, 01:40 PM
So Skip... your daughter has soot in her tailpipe?

ROFL
ROFL ROFL - Soccer playin' pimp strikes another generation of Townes!!!

J Diddy
06-18-2005, 02:07 PM
ROFL

Yup, only reason I own one is for work. It was cheap and fitted my needs.

All my other real vehicles are Fords or Toyota's. :thumb:


:shake:

I like my dakota.

JOhn
06-18-2005, 04:31 PM
I'll PM you with a few questions and see if I can figure it out for you.

Clean out your mailbox :p

JOhn
06-20-2005, 03:52 PM
stumppy ?


Help, I still can't get it running right. :banghead:

Skip Towne
06-20-2005, 05:57 PM
My problems continue as well. She took the car to Autozone to have them diagnose it and their machine was incompatible. So I think I'll change the oxygen sensor first. But I don't know where it is. It is a '94 Grand Am 4 cylinder. Anybody know?

Brock
06-20-2005, 06:00 PM
My problems continue as well. She took the car to Autozone to have them diagnose it and their machine was incompatible. So I think I'll change the oxygen sensor first. But I don't know where it is. It is a '94 Grand Am 4 cylinder. Anybody know?

It will be on the exhaust manifold, usually right above where the pipe hooks up.

Skip Towne
06-20-2005, 09:27 PM
It will be on the exhaust manifold, usually right above where the pipe hooks up.
Thanks, man.

C-Mac
06-20-2005, 09:49 PM
Thanks, man.

Before you replace it, you might just unhook it and see if it makes any difference. If it does, then go to plan B.

Skip Towne
06-20-2005, 09:57 PM
Before you replace it, you might just unhook it and see if it makes any difference. If it does, then go to plan B.
Good idea, I'll do that.

JOhn
06-21-2005, 02:58 PM
Good idea, I'll do that.
Did you get your vehicle fixed Skip?

Skip Towne
06-21-2005, 05:24 PM
Did you get your vehicle fixed Skip?
Not yet. We live 50 miles apart and I haven't gotten back up there.