another damn prob.. plz help

[traser19]

ill first start up my car in the morning.. it will run fine, no issues, no any thing,, ill drive it for about 30-an hour and then the car will start running like s***.. backfireing, and sometimes ill stop at a red light and then go wen its green and i accelerate super slow, like i can pretty much run faster then the car accelerates, so ill floor it, change to seccond, floor it and ti will still go super slow, i highly doubt i have a boost leak because the boost gauge inst showing me any improper readings, besieds the fact that i vacume at 18-18.5, i tightent all my intercooler piping, changed all my vac lines, and its still doing it, i dont know what the problem is


btw*** i have reflasehd ecu, and i had my unichip hooked up and it still does it with or without the chip

 

[mryellermp5]

have u tried resetting the ECU? disconnect battery press brake a few times wait about 10 min and reconnect battery...and have u checked or changed ur spark plugs lately?

 

[traser19]

i have changed my spark plugs about 2-3 months ago but ill go recethe the ecu right now thx

 

[Import1]

problem help

The problem sounds to me like the exhaust is blocked. A car I worked on once had the exact same problem and that turned out to be the problem. Usually from pieces of the cat. break off and block the exhaust.

 

[traser19]

wouldnt that constantly be affecting it,, not just after the car warms up a abit?

 

[traser19]

ohh ya.. at around 3k rpm the car sounds like the exaust is at 5k rpm.

 

[msp35]

I think that's a low vaccuum reading. Most are between 20 and 24.

 

[crashkelly]

I think that's a low vaccuum reading. Most are between 20 and 24.

werd, the higher the better but most have 20-24hg. Sounds like your cats are clogged since you already addressed the plugs.

 

[traser19]

could this also b due to a boost leak???


i just pulled out my o2 censor from past my catalytic convertor, and there was a small dent in it. it looked as if something hit it. but no cel.. i was going to do a exaust back pressue test but i coulndt get to the 1 on the mani

 

[mspHtown]

i have the stewart warner gauge and it reads as his does. i hooked up another vacuum gauge for s**** and giggles, and it read 21. ive read that quite a few other ppl witht he stewart warner gauge have lower vac readings around 18.


wut psi are you running. if i gun it in first the car feels slow as s***. the tires just spin... they also spin a lil into second. you can honestly remember what your exhaust sounded like at 3k and 5k and notice a reasonable difference in what you hear now?!

 

[crackerjakx]

Might be a bad cat. Usually will start to show symptoms as the car gets hotter.

If you have a boost gauge you could probably check this by running the car till it starts to show the symptoms you mentioned. Then try blipping the throttle in neutral and see if it takes long for the needle to drop or run the engine to 2500 rpm and hold then see if the vac reading is around near what it would be at idle.

 

[msp35]

You may have lost some of the screws to the butterfly's in the IM. IIRC
it is a common problem on some FSDE's.

 

[1moreMPH]

blocked up cat, or IC piping leak? and is that vac reading while your AC is on or off -- cuz it seems low?

 

[traser19]

i think i may have found the prob,, it was a boost leak comin off the ic,,, but yes my vac reading goes to about 12 wen my ac is on

 

[traser19]

DAMn its doing it again... might be my catalytic conv then,, s***,,, also the o2 sensor past my cat has a dint in the head of it,, but my cel dosnt come on so i dont think its screwed up

 

[traser19]

just replaced the spark plugs and problem still exists

 

[traser19]

i might have found the problem once again,,,, i sprayd break clean on my MAS and i changed my air filter,,, could this have been the problem?