My car starts and runs perfect when it's cold. It cranks up with barely a hit from the key. After it reaches running temp, ~180, that's when it starts to stumble. But it stumbles up, it idles at 1k and it will jump up to 1200 for a half a second and then back down to 1k once it's warm. Doesn't sound like much but when I'm driving in 1st or 2nd gear it causes the car to jar forward, jerking your neck a little unless I ride it lightly with some clutch. Also, I notice a slight power deficiency especially when climbing hills. As stated previously, the car runs awesome when the motor is cold. I filled my tank up on a military post with 92 octane and washed my engine bay out. I had to get the car looking good for the Pro-bowl game. It was once I was driving to the Pro-bowl that I noticed that the car was running like crap, like a stumble...I guess.

I check my wires and pulled my plugs. They all where clean with a slight ting of white, I was hoping that one of them would be fouled but as it turns out they were all pretty clean. The car kind of acts like when I have a plug wire loose once it warms up. I pulled the distributor cap to see if maybe that too was fouled but it was clean and dry. I Googled symptoms of bad gas and they really didn't match my issues. I have a carb set up with no smog equipment. I was just going to run out this tank of gas, change out the filter (which still looks clean) and put in some fuel cleaner unless I someone tells me that I have a different issue.

http://youtu.be/luGl1PrVpEA

I attached a video, you really have to use your imagination to see it, but it stumbles forward a few times in the video...if that makes any sense.


James

 

Check your intake bolts. You can use carb cleaner or (propane with a hose) to see if it alters the idle. A little "sea foam" and a new fuel filter can't hurt.

 

I know this doesn't match all of your symptoms, specifically the increase in RPM's, but it does match the stumble when hot, check to see if the coil might be leaking oil and overheating.

 

i never had bad gasoline, but Id say that would be constant crap not stumbling.
check what the lads said and on top of that see if you're dripping fuel inside the carb

 

At present my coil is mounted to the engine head. It's been there for about 20k miles, could that be the issue? I'm going to test the coil tonight after work and most definitely mount it to the wall instead.

James

 

Omg. I just came back from lunch and popped the hood and found a dark ring of dust/dirt around the top of the coil....I just detailed the engine bay last weekend so...it must be oil leaking! You guys are on it in this forum. I'm going to replace the coil tonight and post my findings.

 

That didn't fix it. Once the engine gets up to operating temp it sputters about every 10 seconds and again have decreased power when driving. I'm going to run through the tank of gas and see what new gas and filter do.

 

i thought as well that your stumble was rythmic
that's why I thought it might be related to gas dripping in the carb

 

It sounds like the choke isn't fully opening.

 

I liberally sprayed carb cleaner all over the place, no vacuum leak.
Replaced the fuel filter.
Replaced the coil and mounted it from the head to the side wall.
Put some "Sea Foam" in and ran through a tank of gas.
Checked and re-gapped all the plugs to .040 (found some were 35ish and some were 45ish).
Tightened the serp belt (who knows).
Checked the distro cap for water or for missing posts.
Cleaned out the carb, changed out the metering block gaskets, changed the power valve and gasket, changed the accelerator pump rubber thing.
Took apart the choke, cleaned it up, looks like it's in good working order.
Checked the thermostat, put it in boiling water and it works.

All that didn't do it. I came back today and decided to re-check the plugs. I took the plug wires off and checked the resistance just for the hell of it and....I found one that was broken somewhere in the middle, with resistance up to 200 ohms while the others were at 80-90 ohms depending on the length. I replaced that wire but I can't start it up because I have to wait for the gasket to dry on the thermostat housing. I think that the wire was it.

We'll see tomorrow.

Thanks for the tips on how to solve this conundrum.

James