Trouble with my car!!! Need some help!! Already searched

[94fbody34]

Just so everyone knows I already tried a search and didn't find what I was looking for. I have a 94 camaro 3.4 and it seems to be running rough. When I am idiling through a parking lot or going slow my car seems to jerk at random times. It feels like a misfire. Also, when it is warming up in the morning sometimes after about 5 minutes it stalls, WTF!! I have been getting terrible gas mileage, Like 160 miles per tank and it is not my driving because I don't drive my car hard. I connot figure out what the deal is. I took it down to autozone to put the scanner on and it's not throwing any codes. If the car was misfiring or needed a coil pack or anything like that would it throw a code??? Any help is greatly appreciated!!!! [img]graemlins/burnout.gif[/img]

[3.4 slow to go]

when was the last time the car had a quality tune up?

[Arwinder]

Yeah, right now i have a similar problem. My car is stumbling alot so i took it to Autozone about a hour ago for there test and came with a code P0306 Cylinder 6 misfire, bought a spark plug and have yet to put it on. Tune up is a good idea also.

[94fbody34]

I changed the oil and filter about 100 miles ago. The last time the plugs and wires were changed was before I bought it (august of 04'). Plugs and wires were my first thought but I took the plugs and wires out, checked them, and they were all in good shape.

[Need4Camaro]

Originally posted by 94fbody34:
I changed the oil and filter about 100 miles ago. The last time the plugs and wires were changed was before I bought it (august of 04'). Plugs and wires were my first thought but I took the plugs and wires out, checked them, and they were all in good shape.

You getting an SES?

You may have a bad O2 or worse, bad EGR Valve...

[Die Ford V8]

EGR and vacuum problems just screw with the 3.4 regardless i would change the plugs. although you may have replaced them a few months ago, one soaking in gasoline and they will never perform the same again. believe me on this. the guy that told me has built engines for 30+ years, although i dont remember exactly what he said about it his conclusions were legit. you cant just file them or whatever, also they are cheap and in your car it will take less than an hour.

also, our wires burn like crazy so check them thouroughly, if all else fails pop the hood a night when its pitch black and look for arcing of the wires, or ha ha get your buddy and have him feel around the wires, if you get new wires again, go performance because they withstand heat WAY WAY better.

also, check your coil packs. the only way i know is to hook a spark tester to a plug wire and ground it out on the frame. this will show the voltage and continuity of the spark for each cylinder #.

run some seafoam through it and see if you can find an intake manifold leak or other leaks in your vacuum and exhaust system. smoke will pour out of leaks.

four bolts hold on the catylatic converter so pull that off and see if it is plugged(hold up to light and see if you can see through the screening) heck you imght as well take an airhose and clean it some or just punch it out and put it back on. it will give noticable hp gains and better mileage.

gettin 160 per tank would make me think your cat over anything.

also, let us know how your car accelerates and things like that. im sure its egr, vacuum related though.

new plugs for $12, spark tester $5, gutted and checked cat for free, you cant loose after checking this stuff out so start there and keep us posted.

oh yeah, i would get new o2 sensors if you havent had them in a while. the way your car is running now makes them worse anyway.


before you do anything though jsut check generally to make sure all your plugs are plugged in and everything is where is should be.

good luck

[Die Ford V8]

almost forgot, check your air cleaning system too. bad filter wont affect it that bad, but for $6 you might as well change it, just look for obstructions.

[94fbody34]

The car isn't showing an SES light... I will try everything you said DIE Ford V8 (I love your username by the way) :D What is seafoam I haven't heard of it. The car accelerates fine, but ever since this problem has occured it has been extremely slow taking off from a light. Since I live in michigan and we have no inspections I was thinking of just getting rid of the cat all together. The only thing holding me back from doing that is I have heard you lose some low end torque.

[Die Ford V8]

nope no low end torque lost AT ALL. I will tell this to everyone from experience and from asking 30+ years of experience on performance engine builders you will not loose torque from freeing up exhausu except maybe no manifold whatsoever. on inline six fords and chevys i have seen losses in lug torque but the 20+ hp gain was way worth it.

i did this to my friends 94 firebird and not only did it make his car quicker with better mileage but his stock exhaust sounds kinda beefy, not as much as a performance muffler, but pretty darn good for a free mod.

his car is even with my car till he hits second gear. and mines a 3.8 and he doesnt know how to drag at all. seafoam just cleans your engine, frees up carbon and releases stuck valves (supposedly) buy two cans and run one in your gas and one into your brake booster line. dont let your car run with it in there. it will spuder and spuder till it dies, but if you goe through 2/3 of a can(dont do more than that at a time, well i wouldnts) then just shut your car off and wait 10 or so minutes. fire it up and your car will most likely smoke like crazy for a while,(if you dont want neighbors to think your car is crap dont let them see the smoke. they will ask you for weeks if your car is going to blow up and noone ever knows what seafoam is.

you may need a friend to hold the gas so it wont die on you once you pull the line off. its easy, for any more info on this search. there are millions of threads on seafoam. also, look for those threads by me and the insecurities of doing it that i had will probably help you.

WITHOUT A DOUBT YOU WILL GAIN HP AND TQ FROM PUNCHIN OUT YOU CAT. No sensors after the cat to so its a totally worthwhile free mod. just make sure you get allllllllll the screening out. i need to go, but will check the threads later this weekend or monday so good luck.

the typical problem of the 3.4 idle egr, vacuum leak stuff hasnt really been figured out like most other problems so maybe you might figure out the answer.

just an FYI on my friend car I unpluged the passenger side o2 sensor so it would give its stored readings instead of bad bad readings. it helped the idle problems quite a bit. but when he gets new o2 sensors im sure it will run better.

again good luck and happy troubleshooting.

[FunkZ]

3.4 won't throw an SES unless you set off a bomb under the hood, or seemingly something catastrophic. A malfunctioning EGR usually will though.

A coil, wire or plug that was in bad enough condition to cause fuel mileage that poor would be blatantly obvious as a huge reduction in power, and would more than likely hesitate at any rpm. None of those would likely cause an SES.

If I had to guess I'd agree with DieV8 and suspect the cat is clogged. The other thing it could be is one or more leaking injectors.

[94fbody34]

How can I tell if the cat is clogged up?? I looked under my car at the cat and it looks like it's welded on...

[defrag]

Originally posted by 94fbody34:
How can I tell if the cat is clogged up?? I looked under my car at the cat and it looks like it's welded on...

if you bang on the cat with a rubber mallet and hear things rattling around in there, its shot

[FunkZ]

Take it to an exhaust shop or most garages and have them do a backpressure test. They drill a small hole in your Y-pipe or directly in front of the converter, insert a sensor that determines how much backpressure is present, and can tell from the reading if the cat is clogged. If I remember correctly ~3psi is normal but anything 5+ is clogged to the point of hurting performance.

[94fbody34]

Well today I bought a can of seafoam and planned on trying it out on my car, But after reading posts about the product I am a little worried about using it. Somebody said it created problems for their car instead of helping it. Should I still use it, by the way I have 99,000 miles on the clock. Any specific way I should use it???

[mike h]

my 3.8 was showing a SES and misfiring. my o2 greatly improved the problem, but a new fuel pump may be needed. why do the fuel pumps be so hard to get to?