Ok this used to happen once in every blue moon and then this past week on my way to Vegas it happened really bad and now wont go away. When I am going about 65-70mph I lose throttle response, as in I push on the gas and nothing happens and then boom. It backfires. Obviously the backfire was me giving it more fuel but why does this happen in the first place? If I went 55mph its ok, so thats how fast I went all the way to Vegas and back home. BTW its about 290 miles. Aslo from a stand still I would rev the engine and this happened with 2000 to 2500 RPM range. Lose throttle response and then backfire. Any help would be great. Thanks

 

Either your fuel pump is going or the filter is plugged.

 

Really? Wouldnt it happen all the time though if it was?

 

Have you changed out your spark plug wires? I had something similar happen (not on my IROC, though)--the wires looked okay, but a couple of them were bad. New plug wires fixed the problem.

 

Yes I have. When I got the car it was completely stock, and this issue happen probably once when I got it. Then I started doing mods and I got the jegs TPI power tune up kit. I came with a new coil, cap and rotor, and MSD 8.5mm wires. So I didnt think it was that.The fuel pump[ was changed about a year and a half ago and the fuel filter was changed about a week ago.

 

How about the ignition module in the distributor? I know they're usually "runs or not", but they're not hard to swap out (compared to the fuel pump!)

Good luck

TA

 

Don has had to troubleshoot a few ignition modules that did intermittant failures instead of "runs or not."

 

Update: Well I drove my car today on the freeway a good 15 miles and it didnt happen. I dont understand why it comes and goes. Hmm by the time I was about 80 miles into vegas are when the symptoms occured. This is all really frustrating

 

On our car cruises during the hotter times of the year some of the cars experienced what I would call "vaper lock". Hard to believe with a fuel injected car but a little bleeding of the fuel lines and all was well.

 

Actually when it happens it usually happens on hot days. So how do you bleed the fuel lines?

 

Either use a rag wrapped around a small screwdriver to press the schrader valve under the plenum on the passenger side, or crawl under the car and loosen the connection going to the fuel filter.

 

Ok something I noticed when my problem was happening was my oil pressure was going down, but never in the red so I didnt think too much of it. Now the average point was always a little over the last line (60) then it would drop down to the second to last line (45). Figuring the sensor was off I replaced it and it now reads about 30 at idle and 45 when accelerating at highway speeds. When I searched about how to replace it I read that it has the ability to shut off the fuel pump. Is this true and do you think this could of been it?

 

It might, but I've also heard about guys running out of oil and not noticing the oil pressure gauge until the engine failed. In those cases the sensor was perfectly happy to let the engine continue to run until the engine seized!

 

Well today on the way down to Huntington Beach my car finially died. The camaro is now at the mechanic and I should have word on the problem tomorrow.

 

Apperently it was the ignition control module. Good job Troy. Sooooo do you guys think this was the problem the whole time?

 

could be.. or the real problem may have yet to reveal itself.

might be time to bust out the dvom and test your Throttle Position Sensor as well, what your talking about could be a flat spot in the throttle. kind of a long shot, but i always start there when throttle response is funny.

when i had this same problem... i can't remember what it was. dang.. well that was a big help. oh! it was my MAF.