You read the title right! My brothers car is a 97 Cobra with the following mods a P1SC intercooled, bassani x-pipe, Mac Cat-back, Lightning 90MM mass air, 42#inj., MSD DIS-4, 255high pressure high volume, Aeromotive regulator, and 4:10 gears! We started of with the installing of the charger and it was easy no problems and now the tuning bit! We started of with a mail order JMS Autologic chip and a matching 80MM Pro-m Bullet that was requested by them to have instead of using the Pro-M Univer that we were going to use. That chip didn't help out all, we decide to bring it down to Murillo Motorsports, because he said he would be able to tune it alot better that was on 12/10/03! We got it on the dyno and sure enuff it was running rich especially in the higher upper RPM range! Mike Murrillo said that it was dumping at least 40percent of fuel on the top end by the end of the afternoon we had change the plugs on the car and still it was dumping fuel at the top end. By the end of the day Mike decide to switch to the Lightning mass air meter and it was still dumping fuel at the top, everything was working fine below 5000rpm’s but anything past that the car just started backfiring and sputtering cause of all the fuel. Well by now it’s time to close up shop still problem not solved as to why the car was sputtering, he had tried everything all afternoon he even shut off the O2’s just to make it even work right, but still problem not solved. So we left it there for him to tinker with it more, and the only thing he found was that the IMRC plates were not opening right at one point they weren’t opening at all! He fixed that but still problem not solve, he even changed out the computer to see if was a bad computer but it was still doing it! He found that a fuel relay module was shorting out and replaced that, still problem not solved! Well he’s had it for over a month and we talked a couple times on the phone he even told my brother he was on the other line with Mike Wesly trying to solve this problem but still no solution he even took the charger off to see if that was it and now it’s sputtering without it but I think maybe it’s due to the 42#injectors. Well anyway he’s stumped because it stopped doing it up top but now the car is dumping fuel at like 4500 rpm’s and now it’s backfiring even worse! He has just given up on it and basically told us to come and pick it up! I’m pretty upset because not only are we taking a Cobra home that is not even tuned but my brother has $1200 dollar bill to pay with nothing to show for it but a sputtering Cobra! If anybody has any bright ideas or clues as to why the car is doing this maybe I can tell Mike something he might be overlooking, cause we are going to pick his car up this Wednesday!
Thanks, Jon
Thanks, Jon