Just got my car back from the shop, subframe connectors welded on. It drove fine on the way home. I let it sit for 2 days and started it up. Started just fine then the fan cut on and the idle went up and down and just cut off. I removed the battery cables and let it sit for 15 min, put them back on and the same thing happened again.
It starts just fine but idles rough, I give it gas and it's very rough and then the fan comes on and nothing, it just dies, unless I keep my foot on it.
The plugs/wires/cap/rotor/coil are new and the fuel filter. Battery is a new Optima red top.

Could this be my fuel pump?

EDIT


I just started it up, idled rough, gave it gas hard and it stumbled for a bit then smoothed out. I turned the lights out in the garage to look for any spark and I noticed my spark plug boots including the coil wire are glowing blue under heavy throttle. ?? No arcing, strange but not the problem. It acks like it's getting to much fuel.

EDIT

Let it sit over night, started right up but idles up and down to the point where it almost cuts off. It looks like fuel is puddeling on top of the butterflies at idle. Maybe the fuel pressure regulator is bad???

 

Anyone???

I ran a code scan but came up with nothing.

 

Can someone at least give me a quick walk threw on replacing the fuel pressure regulator? I've never done it.

 

Checked all the wires and vacuum lines they look good. The egr diaphragm seems to be working right. The up and down idle has dissipated quite a bit. Tried to drive it and it wont even make it around the block.
Since I can't even get a response here I'm going to the junk yard to get a used throttle body. Ill clean it up and throw it on and hope for the best.

 

I pulled a throttle body off a 5.0 Cadillac for 20$ and its complete and was untouched. I wasn't sure if it was the same as mine but I couldn't pass it up.
I examined it and it looks exact except for the casting number on the top of the fuel pressure regulator housing. The one on my car has a 68 the one off the caddy has a 64. I'm not sure what that means, can anyone here tell me?

Like I said it looks exactly as mine does. And the only reason I even looked under the caddys hood was because of the 5.0 litre badge on the deck lid. All of the other Camaros were 6 bangers and older quads w/5.0 HO motors and cross fires. I was surprised by how many Camaros and Firebirds (3rd gen) they had considering they opened up less than a year ago.

Anywhoo, I hope someone knows about that casting # and anything else I might need to know.

 

The up and down idle has gone away.
I removed and cleaned the IAC and it helped a lot, but still has a skip in the idle. It will start and run just fine, well sort of.
I did make it around the block, improvement!, but it only has half the power and sputters a bit. No engine codes though.

I did take the TBI unit apart from the Caddy I bought for 20$, it just to experiment with and gain some knowledge to apply to mine own TBI. Doesn't seem to hard to totally rebuild. I didn't get to the injectors though.

So, am I missing a step with the IAC removal and reinstall. I was careful with it and used tbi cleaner. The thing still runs like a out of tuned 4 banger....

 

I dont like fuel injected cars very much sounds like it might be a sensor. did you talk to a local auto zone guy or anything.

Hope someone on here can give you a little more info.

 

I have the code scanner, no codes. If it was a carbed motor I would be ok, I can fix those. It's all the sensors thats got me confused.

 

take of your air cleaner and watch the injectors squirt out the gas see if its steady or if it flows out real fast then goes slow let me know what you get.

 

It does seem to change. It's not a steady cone spray, more of a dribble or like rain drizzle. The motor does stumble while I'm giving it gas.

 

does your motor seem to be runing rich if so pull a couple plugs and see if there black.

when your on the gas is the spray steady.

 

Sometimes rich sometimes lean. And the spray is not steady from both injectors from what I can see I may be wrong though.

It's weird, it acts like it runs rich then lean. That would tell me the fuel pressure regulator is acting up, but I cleaned the IAC and it acted totally different. So it has me wondering......IDK.....

 

sounds like the injectors might be cloged when the car is idle it should be more like a mist coming out. go to a local parts store and try and get some sea foam to put in the gas tank. read the directions on back and put in a little extra than what it says but not to much. see if that clears it up at all.

 

Did that 2 months ago. Sea Foam is the best for cleaning out old carbon, but it may have screwed up my sensors....

BTW-I only put about 50 miles on my car since the Sea Foam....I did it threw vacuum line very slowly and only about 5 ounces...

 

i'm thinking a couple things.

1. TPS

2. if your plugs are black from running rich oxygen sensor (should throw out a code but not alway) or you can just try taking it off and cleaning it good with brake cleaner and see if it helps at all.

 

look for a vacuum leak

get a fuel preasure gauge

bump the timing around

check the tps