Hey, guys.

My problem is my CEL come on along with the hesitation at all RPMs and at idle when my car has warmed up.

I start it up, let it idle for 10 minutes. It idles perfect and runs perfect for the first 10 min or so.

Than my CEL comes on and it studders.

Also, lets say I am in third gear.

I step on the gas, it boost builds normally (almost faster then when it ran fine and the BOV is louder too), but my RPM climbs slllowly, and I am not increasing in speed compared to when it runs fine.

How can my boost build, when I am barely increasing in RPM and speed??

What causes the CEL to come on at a certain temperature?

Please do say it can be anything, because only a few things will cause my car to run like **** when it is warmed up.

I changed plugs and wires. I changed MAS, and I changed ECU.

Nothing helped it.

Thanks in advance.

 

I throw some O2 sensor problem... guessing
The best way to know is with an electronic device.

 

Yes, but an O2 will not cause your car to stumble.

It will give you poor gas mileage.

It's usually for emissions purposes only.

Thanks,
Jon

 

O2 sensor is used in closed loop operation.. But we can't help you much unless you pull the code.. It sounds to me like there may be a problem with the MAF sensor or one of the three sensors on the MAF unit itself.. Check the wiring harness and make sure its connected fully, and doesnt appear to have any damage.. Also, is your car modified, and if it is, what was done to it?

 

I got the codes pulled.

9 of them.

MAF
Coolant
front o2
IAT
CAS
Coil 1-6
coil 2-5
egr
vss

 

It's not the MAF, and its not the ECU. I have swapped them both... and it ran fine in the other person's car. The swapped ECU worked on my car, but i was still getting the CEL.

Jon

 

I ordered some EGR block off plates for my car. I will be doing a vac reduction this sunday.

Jon

 

car is just BPU.

What was weird is that I put some 93 non ethanol gas from IL and on the way home on the highway, the CEL came on.

Jon

 

oh the o2 will make your car run like crap, had one go out on my talon and it would gurgle and sh*t so you might wanna check that out.

 

really?

my friends 96 talon tsi has his CEL go on because of his O2.

But his runs perfectly fine. it's just that his car gets ****ty gas mileage cuz of the ****ty o2.

Jon

Can the o2 be fine when its cold and ****ty when it is warmed up and cause my car to run like **** when its only warm?

 

what the heck. we cant swear?

lol

jon

 

Take off all your Bpu parts off and take your car to the dealership for troubleshooting. I would even have a compression test done, you're having too many CEL's. This isn't something can be trouble shot on the internet.

 

Wait a minute, did you have CEL before you put this gas in.... If not, then theres your problem. It's bad gas............................................... .....

 

sure it can

Any help is better than the dealership. I don't want to take it there, they will **** up my car

Jon

 

i just need to know if a bad 02 can cause stumbling.

If it can, i am sure it's the O2.

Jon