Car Help?
 

I know there are some knowledgeable car guys on here, and maybe someone can help. My 2001 MR2 Spyder has been running really rough, and I've been running in circles trying to fix it. The previous owner installed an aftermarket turbo with custom headers and exhaust, K&N intake, piggyback ECU, anti-knock system, and higher flow injectors. I've had it for 5 years and it has been working well until recently, so I don't know that the issues are directly related to any of the modifications.

So far I have replaced the fuel pump, fuel filter, fuel pressure regulator, fuel injectors, coils, spark plugs, camshaft sensor, crankshaft sensor, MAF sensor, and O2 sensors.

It was simply running poorly (sounded like it had a dead cylinder) and not throwing codes, but after replacing the camshaft sensor it started giving codes again. Now it gives codes for misfires on all 4 cylinders, plus random misfires, and says the system is too lean.

I am about out of ideas and hoping that I'm overlooking something obvious.

Can you post the codes?

sounds like a big vacuum leak somewhere...

Not at the moment, I'm at work and the car is at home.

Hmm...

Edit: i cant read

Yeah, test the vaccuum. Do you have a hard time holding boost or building up to the proper psi?

Check all of the connectors on the vaccuum lines. They like to break right where the hard plastic nipple meets the bigger plastic part.

You can buy a vaccuum tester for relatively cheap (and it can also be used for removing brake fluid).

This. With all that aftermarket stuff installed, it seems very likely.

Start the engine, get a can of carb cleaner and spray around vacuume lines. If the engine throttle changes, bingo.

If not, EGR/Purge canister maybe?

I've had the same problem before, taste the gas to make sure there isn't sugar in it, and if that isn't the problem then sink it in a river and report it stolen

Bad distributor?

Just be careful and don't spray too much. You can start a fire by doing this.






Not that I would know anything about that....nope.....nothing at all. But it did happen to a friend of mine....yea, a friend.

Have you ck'd the antifreeze ?

Good idea.

Doesn't have one, coil on plugs.

And you checked all the coils already?

Yes, that was my first thought, as this car went through a phase where it liked to eat coils.