can someone help with me some problems? i recently installed ported polished LT1 heads and lt4 hot cam kit.

the car would stumble and hesistate at low RPMs. so i switched the plugs out, installed NGKs. i was coming to work today and the car died on me. i turned it on after about 3-4 cranks. drove it to work, but it feels like crap at low rpms. and as i was pulling in the parking lot to park, it died on me again.

what are the posibilites that cause the car to stumble and die? did i mess up the plugs??

 

Seems from what you are describing that your opti is going bad. You may also want to check for a clogged fuel filter.

 

well the fuel filter is brand new. just installed saturday.


i was thinking the opti as well

will a coil cause this?

 

Usually a bad igntion coil will cause stumbling at higher rpms. There is no harm in checking to see if it is good though.

 

Double check the wires on the opti, make sure you have them in the rite place, then follow them up and make your you have them on the right plug lol ...

 

you think that could cause this? cus the car ran good for a day with the tires in the same place.....i mean wouldnt it misfire right away?

 

Yea it would run like crap rite away if you have the wrong wries in place ... i missed the part where you sed it was ok for a day , sorry ... So my next guess is that its running really rich , which would explain why it could backfire ... that would be one of the electronic controlls causing that id think ... SES light on yet ?

 

Have you done the easiest step and looked for a vacuum leak. Any unmetered air after the MAF will cause hesitation.... Could be you missed hooking something back up.

 

i did have my friend check the for vaccum leans and he found none.

might cause hesitation you said right? well the car hesitates, stumbles then turns off...would a vacuum leak cause that?

the car hsa 74K miles...time for a opti?

 

yes it definitely can, but is there a way for you to scan codes. I mean that would be the best way to start your diagnoses. It may not tell you exactly what is wrong, but it may help you figure out what isn't.

 

sounds good. i think i will take to check for leaks..to another friend.


and..how can i test for vacuum leaks?

in the back of the car..near the brake fluid bottle thing, there is a loose small black hose......think that has something to do with it? or is that jut for the air cond.?

 

and for scanning.

well i have an obd1 conversion in my 96.

should i re-install my obd2 computer and run a diagnotic? or that is not the scanning you were talking about? thats the only tool i have to check for problem codes

 

Try unplugging your MAF and see if that helps. I've noticed that if you unplug the MAF when you have vacuum leaks they go away. Now, this isn't a fix, but it will tell you if vacuum is the issue. Also, plug that hose you were refering to when you take off the MAF. If it runs better than I would almost guarantee its unmetered air somewhere. Good Luck

As far as the scanning. OBD I is actually easier to scan. I believe Autozone still scans OBD I for free.

 

so, i unplug the MAF and leave it unplugged, start the car and see if it still hesistates and turns off?

and then if not..i try to plug that small hose i said neat the brake fluid canister and see if that helps?

lets say it dont work..what else can it be?

scooby and everyone else. i just want to thank you so very much.

i want my beast up and running

 

What year is your car and did you have it programmed for the head's an cam? What exhaust are you runnin?? (ie headers?)