Help this prob is making me nuts!!

[Samurai Jack]

Ok I have been working on this for 3 months and cant figure out the problem. First my tsi awd gets terrible (1/2 tank 60 hw miles)
gas milage and my main concern is when I push the pedal any where for 3/4 to full throttle the car shutters a little and backfires till i let of the throttle. It feels like a ignition miss. I have replaced the fuel pump(190 rewired) fuel filter,new plugs, wires( 2 sets to see if they were bad) o2 sensors,coil packs, and tested it many times for
boost leaks. I even had satan try to figure it out while they replaced my timing belt. They spent a day trying to figure it out and then gave up. They also said the injectors were cutting out under full throttle but didnt know why.

My car is a 95 auto Tsi Awd with 63k on it.
My mods are 14b, upper and lower IC pipes, 1g bov,
TMO stage 3 chip, supra IC, 3"o2 housing-exhaust, 190 fp. But I
had this prob with the stock IC, t-25,o2 housing and euc as well.

I have no idea what to do next. Please give me some ideas. Thanks

heres the car that needs your help:

http://www.webphotos.com/list_photos.asp?mi=3&smi=1&a=121792

 

[markgholland]

What kind of boost are you running? Does it start backfiring at a certain RPM? Do you have a logger that you could see if your getting knock? A friend of mine was having the same problem with his 1g; it ended up being that the caps in the ECU were going. Just a thought.

 

[Samurai Jack]

Its at stock boost right now. I does it a higher rpms aroud 6k. I do not have a logger as of yet and when I put the stage 3 chip on it i looked at the caps and they looked(smellt) good. Do the caps go bad on 95 ecus like the 1gs????

 

[1gfromND]

what about the TPS just a thought.

 

[BIGGSIE]

What kind of plugs are you using?? Just a thought

 

[Samurai Jack]

Thanks guys but its not the tps and I just tried 2 different sets of stock ngks and there not the problem. Anyone else?????

 

[Enigma_Man]

Boost leak? Done a test yet?

-Jesse

 

[fwddsmturbo]

Did it do anything like this before th TMO chip, a solder sonnection could have come loose.

 

[Nighthawk01]

sounds to me like a faulty fuel pressure regulator....

 

[Samurai Jack]

It was doing this before the tmo chip. Thanks nighthawk i have not checked the fuel pressure regulator but wouldnt that throw a code?

 

[Nighthawk01]

Originally posted by Samurai Jack
It was doing this before the tmo chip. Thanks nighthawk i have not checked the fuel pressure regulator but wouldnt that throw a code?

but i would also assume the problems you are refering to would throw a code no matter what is causing it .

i would stop throwing parts at it, and check the fuel psi and go from there.

btw,, book says 36psi for manual trans and 43psi for your 95' if it's an auto trans.

 

[Samurai Jack]

I forgot its throwing a egr code too.

 

[hose101772]

Close the gap on your plugs.

 

[Samurai Jack]

I have had them gapped at .032 and .028 and it makes no difference. I wish it was that simple.

 

[Samurai Jack]

Im having some friends come over tonight and try to figure this out again. Any suggestions of things to check would be great. Thanks for the replies guys.

 

[Samurai Jack]

Well we did another boost leak test and there was none. Couldnt check the fpr yet. Still cant figure this out............

 

[Samurai Jack]

fpr is good. Any one ever have a problem like this???

 

[1gfromND]

K well what is the color on the plugs cardboard color like they should be or carboned up? Also have you check your base timing? Just my 2cents

 

[Samurai Jack]

plugs are clean. How do I check the base timing?? thanks

 

[ExtremeImports]

get a timing light, look for the plug/connector with a cap on the firewall next to the battery and ground that out on the battery. This bypasses the ecu from correcting the timing. check to see where its showing by looking at the crank pulley and you will be looking for a small (dot) and the markings on the pulley. It should be about 5 deg before top dead center (BTDC) and that will tell you if its out of time. You can adjust the base timing off the cam angle sensor on the head.

Hope this helps... i should be correct on how to do this.

 

[Samurai Jack]

Timing is fine. I cant figure out why the injectors are shutting off around wot.

 

[Samurai Jack]

I just checked the TPS and its good. plugs,wires, coils are all fine. No boost leak what so ever. What else should I check. New fuel pump 190 rewired and new fuel filter. Maf is fine. Im out of ideas

 

[AL92]

Well after the basics of plugs and wires and fuel filter and checking pump operation and pressure.Then mabye clogged injectors or bad igntiion coil pack.

 

[larryriverside]

i have a 1g with the same problem. it feels so much like an ignition problem. my timing and fuel are perfect. then pulse width goes from 19.whatever to 15something. but is goes in the 15's right after the misfires begin. i am thinking if it wasn't getting fuel my engine would be toasted by now. its been bothering me for a while, but today got a little worse. damm:thumbdown

 

[Samurai Jack]

Could the injectors be really clogged or bad?? Would bad injectors throw a cell? Coils are good. thanks