Team Camaro Tech banner

1 - 20 of 35 Posts

·
Registered
Joined
·
12 Posts
Discussion Starter #1
ok i have a 1989 camaro 3.1L one day when i was driving and stopped at a red light, then tried to drive off it only gave me 30% peddle then after that it would stumble and sputter and almost back fire. i have taken it to a shop and they dont know whats wrong with it after 3 weeks.

shop replaced: computer, spark plugs and wires, coil pack, fuel filter, idle controll senser, and many more cant think of it right now.

please help i need my camaro back :(
 

·
Premium Member
Joined
·
352 Posts
Its a pretty new car but does it have a TPS (throttle position sensor) like my foreign race car:cool: if so check that:popcorn:
 

·
Registered
Joined
·
5,277 Posts
A major vacuum leak that fools the mass air flow sensor (MAF) or the manifold abosulte pressure sensor (MAP) can cause some pretty weird behavior. Look for large vacuum lines that may have been blown off by a back-fire. The break boster and PCV hoses are suspect. Also, if you have a MAF engine and there is ductwork between the throttle body and the MAF, make sure it hasn't slipped apart or developed a crack along a seam.

I hate to see you throw so much money at it though. Most sensors can be verified before replacing them. It requires a volt-ohm meter. A couple of straight pins (like you find in new clothing) can be used to back-probe the connector in a live circuit. A couple of aligator leads help connect the back-probe pins to the meter. Most sensors have 3 wires. The outer wires are usually hot (+5V) and ground (0V) with the center being the signal wire. A couple of quick checks with your meter will help you figure out which is which. Often times starting the motor and operating the throttle by hand while looking at the meter reading (set on DC volts) will help you find a dud sensor. Voltage changes should be smooth with no abrupt changes in the reading. A MAP sensor can be operated by a hand vacuum pump (if you have one of those) while watching the meter change with vacuum level.

And finally, those 80 models were well known for bad connections - even in the 80s. Imagine what nearly 20 years has done to the metal pins of the connectors. I've fixed several issues (on those model years especially) just by brightening up the connector pins with a tiny piece of rolled-up sandpaper. A small pick probe or even a brad nail can be used to squeeze the sockets closed a bit. Finally a nice dob of dielectric grease will help keep them corrosion free and will provide some moisture resistance. That's probably the best advice of all. It's cheap, easy, and no paid mechanic is going to invest that level of care until they've racked up a huge bill in replacement parts.
 

·
Registered
Joined
·
60 Posts
I agree with the timing issue. its too often i see that happen. Its expensive to do but if that thing has a timing belt instead of a chain, than its more than likely. OH! and dnult is a down right serious caretaker for his car. I love my camaro just as much as he loves his. Haha good luck eric! :cool:
 

·
Premium Member
Joined
·
3,159 Posts
Did you pull any codes?
 

·
Registered
Joined
·
12 Posts
Discussion Starter #7 (Edited)
ok all the problems yall stated i have checked, and it all normal its not jumping timming at all i checked that first. the TPS has been changed the mas air flow sensor has been
changed and there is no vacuum leaks at all. the manifold abosulte pressure sensor has been changed also. its is at a point where i am about the jump the car it is really bugging
me. :( i cant tell what is wrong with it. it will idle perfect, with no noise or anything.
but when i give it gas it will sputter and try to die out. but soon as i let go of the gas, it catches itself and continues to idle perfect..


EDIT: oh and ya pulled codes and says the engine is running at like 300+ deg. on cold which is untrue lol
replaced the temp sensor/ nothing
 

·
Registered
Joined
·
358 Posts
Sound like a restricted catalytic converter. No power on take off but will idle fine, just went through a job with symptoms as you'res. Replaced the cat and the car ran 100 % better.

Ken
 

·
Registered
Joined
·
5,277 Posts
ok all the problems yall stated i have checked, and it all normal ...the mas air flow sensor has been
changed...
Don't assume that just because a part has been replaced that it is functioning properly. Bad connections will spoil that plan. You'll bankrupt yourself replacing parts willy nilly and may never make the thing run right. You've got to diagnose the possibilities, start with the simplest and cheapest and work your way up to things like timing chains / belts. It's nice when you replace a part and all is right with the world, but it don't always work that way.
 

·
Registered
Joined
·
12 Posts
Discussion Starter #10
Sound like a restricted catalytic converter. No power on take off but will idle fine, just went through a job with symptoms as you'res. Replaced the cat and the car ran 100 % better.

Ken
nope its not that i took the cat off and and ran it straight pipe. and still doing the same thing. i thought maybe it was the cat or clogged exhaust.

and dnult when i said its been replaced i mean i replaced some parts two or three times thinking its was faulty or something and all connectors and everything are fine. i been under that hood for 4 weeks straight and for the life of me i cant find out whats wrong..
 

·
Registered
Joined
·
19 Posts
do a compression check on it. you might be surprised to find out you may have a bent valve, or even bad spring
 

·
Registered
Joined
·
19 Posts
had a dodge hemi in my shop yesturday with a bad valve spring. no codes came up not even check engine light. would fall on its face flat out. acted like in had 3 or more dead holes.......one simple valve spring. a careful compression check will give you a straight answer. and its cheap to check.....
 

·
Registered
Joined
·
12 Posts
Discussion Starter #13
hmm ill try that and i will inform you. the shop doesnt open back up till monday so ya
i hope that is the problem and thank you guys for all the help.
 

·
Registered
Joined
·
5,277 Posts
no its getting plenty of fuel, that was the first thing i checked..
What's the pressure Eric? Visuals are better than nothing but fuel injected engines only work properly in a narrow range of fuel pressures. Without those kinds of diagnostic details you're left to swapping part$$$$$
 

·
Premium Member
Joined
·
9,357 Posts
try hooking up a fuel pressure guage, tie it to the wiper arm and drive your car, see what the fuel pressure is at an idle and at light to medium throttle??..sounds fuel related..when did it start acting up? did somebody put some crap in your tank?..is the car an auto or 5spd??
 

·
Registered
Joined
·
12 Posts
Discussion Starter #19
its at 40psi at idle and when i throttle it up it goes up to like 43 or something its an auto.
it give me the trouble about when i got 30% of the throttle in it stumbles and stats sputtering like its not taking gas. i am going to cut into the fuel line and hook up a electronic fuel pump up and see if that is the problem. if its the fuel pump then it will fix the problem when i do this.


and how do you even get to the gas tank to get the fuel pump out? because from the looks of it i have to almost remove to the whole rear end to even do that...


EDIT: and it just started all of sudden. when i was sitting at a red light tryed to go then nothing. i couldn even give it 2% percent throttle, but after replaceing alot of parts i can give it about 30% throttle now..that will get me to like 35-50 mph..
 

·
Premium Member
Joined
·
9,357 Posts
you need to do a volume test(hook up the guage and run a hose to a soda bottle) ..at an idle ..10-15 seconds it should fill a 16 ounce bottle or so..hold on a minute ill give you the specs.. let me get my 89 camaro book.
 
1 - 20 of 35 Posts
Top