Spipedong90

Today when I was driving home from work I noticed my idle was kind of rough and I didn't think much of it, but stopped at an intersection the tach just dropped and it almost died twice. I made it home without incident. Now, this brings us to now. I started the car to put it in the garage and it barely started and black smoke was shooting out the tailpipe. The engine was just chugging and this smoke was pouring out. It limped into the garage where it choked a while, died and won't start now. WTF happened?! the car was FINE this morning. I was thinking vapor lock or something lame like that, because the weather just changed, but thats not it. Could it be ****ty gas or something? I hope to find something simple, like spark plugs or something. I'm investigating the incident right now.

10:25 All spark plugs are greasy black (Expected) now to find the cause.
10:35 Stupid ECU shows 55 (All Good) which can't be right.
10:40 Car starts but only on the carb cleaner I was using? Keeps running as long as I hold the RPMS about 2500.
11:00 F**K IT.
11:05 F**K IT some more and find the keys to the Volkswagen. I'll deal with this later.

jp91se

maybe someone took a **** in your gas tank when you were at work or something. can't imagine that would do good things to your engine...

5spd92SE

Please click here

Spipedong90

I really don't think I need a new engine.

davis4005

It doesn't sound like you do, if the timing belt broke it wouldn't run, and it's not seized or anything. It sounds like an electrical problem but that should show up on the ECU. The only thing I can really think of is if your tensioner came loose and the timing belt slipped a few teeth wihtout coming completely loose, but I don't know if that it possible. Maybe it's the ECU itself. Good luck man.

Spipedong90

I found out now that it will start but not happily, and run pretty normally if I pump the gas to get the RPMs up to about 2750 and hold the pedal there. If I push it down all the way the engine just takes a dive straight down and dies, and It'll recover if I pump the pedal. This is the damndest thing I've ever seen. I replaced the plugs and the fuel filter which needed replacing anyway, that obviously didn't help. I also bought some gas additive to dry out the tank and some other stuff to clean the injectors. I'm thinking now maybe a vacuum leak or something with the injectors.

eric93SE

iTrader: (1)

Could be your ignition system, check the COIL (also transitor pack), inspect the cap and rotor.

Spipedong90

I THINK I HAVE MADE PROGRESS!

I started taking off each piece seperately starting with the air filter. I have discovered that as long as the MAF Sensor is disconnected the engine runs fine, but bounces off of about 2500 RPM.
I think this may be the problem. As soon as the segment is reconnected, the engine dies. also if I hook up the vacuum hose to that hose segment, the engine dies. So from what I can tell, for some really messed up reason, any air passing through the MAF sensor kills it. This doesn't sound right at all, but is alot simpler than replacin all the injectors.

hahaha I just went and messed with it some more, and if I so much as blow on the MAF while the cars running it dies. WTF is up with THAT?

davis4005

Nice diagnostics man, it sounds like it is the MAF. It's an expensive part, something like 300 or 400 new. Check the junk yards, and good luck.

Spipedong90

Okay. Now I'm really confused and ****ed. I replaced the MAF sensor, and the problem still hasn't gone away. What exactly does the MAFS do? Does it regulate fuel based on the airflow? Could it be that I have clogged fuel lines and the MAF sensor is lowering the fuel rate below what the car will run on? ARGH this is driving me nuts. Any ideas? Obviously any slight breeze on the MAF sensor killing the car is not the way this should work.

eric93SE

iTrader: (1)

Dude you should not have replaced it until you went through actual trouble shooting for the mafs found in the FSM.


First thing to check would be the EGR valve to make sure it is not stuck open and allowing exhaust gasses into the engine while its idleing. You can operate the EGR by hand simply by placing your hand under the EGR and pulling up on the diaphram, lift several times to help free it if its stuck.

But the problem you are having sounds like the engine is running very rich, and the controller for the air part is the IACV (idle air control valve). The valve could be toatlly clogged with carbon deposits and if bad enough it would need to be removed and thoroughly cleaned, rememmber to buy a new gasket. I dont think it is actually necessary to replace the IACV b/c it is controlled by a spring loaded piston that moves back and forth due to a solenoid that pulses a magnetic field. Be carful when removing the solenoid from the IACV b/c the spring can jump.

Spipedong90

I got the part for cheap at a junkyard, and because I go there a lot, they're just going to give me credit. But anyways, according to the ECU in diagnostic mode one, the engine is running lean. I would tend to agree because now the plugs are white and the engine backfires upon acceleration. The exhaust now has that smell that an extremely lean engine has. But this is only with the MAF connected. Without it, the engine runs fine up to 2000 RPM.
This is strange b/c when I first had probs it was like it was too rich. now it's too lean. WTF?! I'm going to troubleshoot the thing for another couple days and then take it to a mechanic. I can't be without my car much longer.