well the car has been running funny for a while now. and i havent been able to pinpoint the problem i keep changing stuff and i still cant seem to find whats causing this. i have the following mods: hotcam, mac headers, off road y-pipe, gms maf and all the other little goodies. here goes. when i first fire the car for the day it pops/backfires while its warming up. then it wont do it again until it cools and then is
restarted. which is annoying but what really bothers me is that it doesnt always run strong either. it will run perfect and then all the sudden it will become slugish and not responsive and loose power. it revs slow and sounds funny( almost as if i added a few more mufflers to the exhaust system). and i dont know if its just in my head but it sounds like the valve train gets twice as loud when its running funny. could i have some lifters that arent pumping all the way up sometimes? or do you think its a computer problem. ive changed the push rods and all of my valve springs, plugs and wires. and ive had it on autotap and have been told that its not throwing any codes, but the ses light does come and go, which i have been told will happen with that cam. but it runs strange no matter if the ses light is on or off. when it first started running this way it only did it rarely, but now it rarely runs good. this has been going on for about 6 months now. and i really need to figure out whats going on. if no one has the solution, do you know of anyone if the bay area that could figure this out? ive had it to Ralphs shop in sac a couple of times(which is a great guy), but hasnt been able to figure out why its doing this. i cant deal with it like this any longer. any info would be great. thanks

sean

 

oh yeah i also forgot that when i nail it in first at about 5200 or so it coughs/pops and then rips up to 6 grand. and i know that its not hitting the rev limiter because it then recovers and climes up. dont know if this is related or not?

 

Honestly, it could be a lot of different things.

Poping / backfiring at idle usually indicates a couple things, Pig rich, or timing is off. Incorrect timing could be caused by a bad tune, bad sensor, or bad cam install. Pig rich can be caused by (oh man, there is a lot of ****) MAF sensor, vacuum leaks, exhaust leaks, bad tune, just to name a few. If your car is stumbling up high when you get on it, then I would lean towards timing, but like I said it could be many things.

First of all, you need to find out what that SES light is. Next time the SES light comes on, don't clear it. It may just be from the Cam generating a P0300 general misfire code, but there may be something else causing the SES (ie too rich / lean, MAF low freq) something that could point you in the right direction as to what is wrong.

And lastly, some logged data during when the car is acting up could really expedite the process and bring your hassle to an end.

Good Luck
<img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" />

 

what should i get to check the codes its throwing and log some data?

thanks
sean

 

I prefer AutoTap, (a-tap) but that software is quickly becoming obsolete. EFI Live is another software that can be used to pull data from your car. There are quite a few more out there.

The only problem with the software is that it is going to be 200 bucks.

If you just want to get the code read, you can go to a dealer and pay ~70 bucks and ask them to record the numbers of the SES codes. You have to ask them though.

Good Luck