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Discussion Starter #1
I was at a buddies house yesterday and we where talking about his car. Its an 86 camaro that his mom has given to him because its broken down. Yesterday I managed to get it running by pumping the throttle.

Every time i took my hand off the throttle or tried to keep it one place it died.It sounded like it was only running 3 or 4 cylinders and i could hear it backfiring A LOT. I checked all the wires and there all in the right place. He says it probably has blown head gaskets (uh o) but i don't see why it was running like such crap.

We went down to the auto parts store and picked up some new plugs i plan on installing tomorrow but I don't think thats going to fix it.


I guess it originally started over heating. But his moms crackhead boyfriend stole it for 3 or 4 months and did who knows what to it (you start it by touching a wire to the positive terminal)


any ideas guys?

If i could get it running we could take it to a shop and find out just how messed up this car is but we need to get it moving first
 

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Discussion Starter #2
Oh. and how hard is it to change the plugs on these things?

doesn't look like fun :D
 

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The 3rd gen F-bodys are notorious for fuel pumps going out. Check the fuel pressure. Usually if you put your hand over the throttle body and the car runs, Its a vacuum leak or it is running lean. I am gonaa say fuel pump. Is it a TPI or Throttle body?
 

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Discussion Starter #4
The 3rd gen F-bodys are notorious for fuel pumps going out. Check the fuel pressure. Usually if you put your hand over the throttle body and the car runs, Its a vacuum leak or it is running lean. I am gonaa say fuel pump. Is it a TPI or Throttle body?
tpi

I had a feeling it was the fuel pump...
 

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Doesnt sound like a fuel pump, with an electric pump, more importantly with EFI stabbing the throttle doesnt mean anything except a flooded cylinder.

The pump will only put out what it can, at ignition ON, there is NO connection to the throttle and the fuel pump. Not like a carb. where you are basically dumping more fuel by pumping the throttle before revolutions.

On a EFI engine it wont keep pulsing fuel with the continuous jab of the throttle if the engine isnt turning. The computer says if the engine isnt turning Im not gonna pulse the injectors any more. Some bad EFI systems will allow a few cycles of the injectors at start up with a throttle poke. Thats where you get a flooded EFI start with throttle. Thats why most EFI systems say dont touch the throttle at start up, possibility of a too rich start, flooded in some cases.

I would keep on your path of plugs, dont forget WIRES, they are very important. After that lets hear some more?? JR

So I just re-read your post, back firing, lean, now I see why the nod to the pump. Can you get it up to higher RPMs by goosing the throttle??? Will it get above an idle???
 

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Discussion Starter #6 (Edited)
Doesnt sound like a fuel pump, with an electric pump, more importantly with EFI stabbing the throttle doesnt mean anything except a flooded cylinder.

The pump will only put out what it can, at ignition ON, there is NO connection to the throttle and the fuel pump. Not like a carb. where you are basically dumping more fuel by pumping the throttle before revolutions.

On a EFI engine it wont keep pulsing fuel with the continuous jab of the throttle if the engine isnt turning. The computer says if the engine isnt turning Im not gonna pulse the injectors any more. Some bad EFI systems will allow a few cycles of the injectors at start up with a throttle poke. Thats where you get a flooded EFI start with throttle. Thats why most EFI systems say dont touch the throttle at start up, possibility of a too rich start, flooded in some cases.

I would keep on your path of plugs, dont forget WIRES, they are very important. After that lets hear some more?? JR

So I just re-read your post, back firing, lean, now I see why the nod to the pump. Can you get it up to higher RPMs by goosing the throttle??? Will it get above an idle???
I can get it up to higher rpms if i keep pumping the throttle but like i said it sounds like its running off 3 cylinders and is backfiring like no other

id say the max i could get it to by jabbing the throttle a bunch is like 1500 rpms.

and i looked at the plug wires they don't look cracked or bad

i also i checked all the wires and there hooked up right too.


I was thinking about pulling off the air intake and squirting gas down the intake. That should tell me if its the fuel pump right?
 

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I wouldn't recommend pouring gas down the Throttle body. I use carb spray. I would have someone crank the engine over and do not touch the throttle. Start spraying above the throttle body as it cranks and the car should start up and idle. Do not put the can right above the throttle body, hold it about 2 feet away and spray it into the throttle body. If it does start and idle. Then more then likely it is the fuel pump. This is in no-way a definite test though. This is just a quick trial and error test. I would really check the fuel pressure out. If it does have fuel pressure, Then it is another problem.
 

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Double check and make sure you have the correct firing order...

pops
 

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MAF sensor

Since you said it was a TPI I suggest you clean the MAF sensor. You should be able to get MAF cleaner at your local parts store. DON'T use anything but the can that says MAF sensor on it!!! The cleaning procedure for it is to remove it spray the wires in it with the cleaner and let it thoroughly dry. Those wires are very sensitive so don't touch them with your hands and don't put it back on the car wet you can short it out. I know that with the 4th gen Camaro's you can unplug the MAF sensor and start the car they'll go into a bypass mode. Not sure with third gens. I have seen exactly what you're talking about being caused by the MAF sensor and it didn't throw an SES code.
 

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Discussion Starter #10
Yesterday we changed all 8 plugs on it they where some of the worst gummed up plugs Ive ever seen and even the 4 new ones on the driver side where caked in grime.

After that it started up and ran but it still wont idol for us. as long as we are giving it gas it will keep running. keep it in one place too long and it will die.

My buddy took it around the block once and when he came back there was lots of smoke coming out of both sides of the engine bay so i figure it has to have blown gaskets.

Also when he drained the oil it looked like it had little pockets of water in it.

My dad also thinks so too because he said when that happens you can burn up your cat quick and his cat is toast

needless to say we have about 1k of work ahead of us that we know of. so no victory cigars just yet.
 

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Oh boy, TPI. I built one of those once. They're great when they work. Ok, A couple things to check. First, check your fuel pressure. There is a port on the fuel rail with a schrader valve in it that a mechanical fuel pressure gauge hooks to. You can probably rent one from AutoZone or the like. It could be a weak pump or a bad regulator. Did you change the fuel filter? A clogged filter will do exactally what you're experiencing. You could have a plugged catalytic convertor, and a peice of catalyst broken off plugging the muffler. that will drop it tight on it's face. If all that's fine, check the voltage reeading on the TPS (Throttle Position Sensor), these go bad all the time. Doest the car still have the stock intake ducting on it? There should be a MAF sensor in the ducting. This could be bad, or if it's missing then you have an issue. Sometimes people who have the cars with a MAF will install a stock replacement K&N filter in the air cleaner, but the oil will ruin the MAF. Check for vacuum leaks. Make sure everything is hooked up. Is there a check engine light on? Does the engine light work? Have you checked for codes in the ECM?
 
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