Hi, new to the forum. Just bought a gen 3 i'm in england but anyway just bought a 1990 camaro rs with a 3.1l v6 auto engine in.

Previous owner bought the car was driving it home fine then he decided to drive it a bit fast and it started this problem and he had to get it towed home.

The car will start but as soon as you touch the accelerator it dies. You can get it to rev if you hold the accelerator down as you start it and if you then feather it you can get it to rev a little bit before it dies. The throttle position sensor has been tried and I just tried a new fuel filter today on it. Makes no difference. If you disconnect the map sensor and it's vac line it still makes no difference.

Any help would be much appreciated really need to get this car to run as i'm stranded without one and bought this hoping it would be a somewhat easy fix.

I'm really a gen 4 camaro enthusiast but I couldn't find one cheap enough so got this big gen 3 that's like a muscle car monster

 

Welcome to the forum. I've found a wealth of info on here to help me with my 3rd Gens. Your situation sounds like one I had with my V6 3.1. It turned out to be my fuel injectors and fuel pressure regulator (FPR). I would check your vacuum connections, ohm your injectors, and ensure your FPR is not leaking bleeding fuel into the vacuum hose. Do a search on the forum or look at some of my posts in the past. Good luck.

 

thanks for the reply, don't want to sound dumb lol but where would I find the fpr

 

It's under the plenum. In front, and on top of, fuel rail assembly. Has a vacuum hose attached to it. Pull the vacuum hose and start the engine. Observe the FPR where the hose connects at least three minutes. If fuel starts leaking then your FPR is bad and needs to be replaced.

 

can I just lift the hood and there it is or do I have to take the plenum off with the special torx drivers etc, hopefully not

 

FPR is circled in red. You will have to take the plenum off to check ohms on fuel injectors though.

 

ok, thank you.

Found the fpr took the vac hose off it then started the car the car ran really bad and cut out without me doing anything after like less than a minute. Didn't see any fuel coming out of the fpr but reconnected it and now when I start the car it cuts out after a less than a minute after running really rough, rougher than it has before.

Not sure if this is to do with the fuel filter being small as had to get a universal on and not the correct one as someone has made it so only a universal will fit. I can change it to a new bigger one or go back to the old one. It ran like it has before yesterday though after I changed the fuel filter. Didn't try and start the car this morning at all just took the vac line off the fpr and then started it.

Any thoughts would be greatly appreciated thank you

 

If the FPR is okay then I would check the ohms on the fuel injectors. I had to take my plenum off to do mine. The good injectors ohmd in the 11 - 13 range and the bad ones were below 10 ohms. I would look into the flow per minute rate of the stock fuel filter compared to the universal. If it is lower that could be your problem as you'd be starving your engine from gas.

 

Hi ok so today I put a new coolant temperature sensor on. The car ran alot better and didn't cut off,until.. I touched the accelerator... urghh but was able to test the fpr and no fuel came out of the vac line bit on it or even looked like it was going to. I don't have a volt meter to test the injectors but just wondering if there is any other ideas? I will be changing the fuel filter over to a new higher capicty high flow one.

 

Also I should mention that the rpm gauge is screwed it goes haywire when the engines running. Like it'll even redline etc but the car will just be idling.

 

Also yesterday I tried this thing where you warm the car n then let it run for a minute then put it in drive then let it idle another minute then put the ac on then idle another minute then turn the car off then wait a minute then switch it on n now with the ac it will sort in an odd way accelerate for a bit before it shuts off. Any help greatly received

 

The fault with the Tacho is pretty common. One of the capacitors probably failed.

Does the engine still cut out if you are very slow with the accelerator?

 

I can kinda feather it and itll sorta rev but yeah eventually it will cut out like its not good enough that you could rev slowly n drive it.

 

I believe it should make a difference if you pull a vacuum off. May indicate you have a vacuum leak somewhere. Too much air will kill an engine as much as too little gas.

 

Anyone suggest checking the fuel pressure? That'd be my first check.

 

I've changed the fuel filter again now n it's made no difference. How would I test the fuel pressure? Also re above could it still be the map sensor then?

 

So you haven't tested it? That's basic stuff before replacing parts.
The picture shows the port & you don't need to remove the to plenum to get to it. Do you have a parts store like Autozone? They rent tools & testers for free.

 

So how do I test it? And what would be the cause of dodgy fuel pressure?

 

Here's what the tester looks like. Pressure should be 36 psi or so running & 44 psi with key off. It should hold pressure.
Low fuel pressure can be caused by a weak pump, an internal fuel tank leak, a weak pressure regulator, plugged up fuel filter, & a fuel line problem (kinked or leaking).