89muscle

I HAVE AN 89GT WITH TOO MANY MODIFICATIONS TO LIST. WELL HERES THE STORY, I BUILT THE MOTOR LAST YEAR AND DID NOTHING TO THE COMPUER, ITS A MX5 2001 EXPLORER 302 BLOCK WITH BRODIX ST5.0R HEADS 1.6 ROCKERS, TRICKFLOW STAGE1 CAMSHAFT, AND THE WHOE 9 YARDS, COBRA INTAKE ECT. AFTER I HAD THE THING DIALED IN LAST YEAR WHEN I WOULD START IT UP IN THE MORNING AND START TO MOVE OUT OF THE GARAGE IT WOULD POP OR BACK FIRE THROUGH THE INTAKE MANIFOLD. BUT ONLY ONCE, NOW THE ONLY MOTOR CHANGES FROM LAST YEAR ARE ONLY A120AMPALT.ANDLONGTUBESANDMATCHING PROCHANBER H-PIPE. IN OPEN LOOP IT RUNS LIKE A SUPERCHARGED CAR, BUT UNDER NORMALCONDITIONS LIGHT PPEDAL PRESSURE IT POPS AND BACKFIRES LIKE CRAZY. ITS AT THE DYNO PLACE AND THEY HAVE BEEN PUTTING PROGRAMS INTO IT LEFT AND RIGHT BUT ANYTHING LESS THAN W.O.T ITS GOING NUTS! THEY ARE USING A S.P.I COMPUTER CHIP. NOW WHEN I BOUGHT THE CAR THE GUY SAID THERE WAS A CHIP IN IT BUT I ORMY MOTOR GUY SAW OR COULD FIND ANYTHING. DID THEY USED TOMAKE AN INTERNAL CHIP THAT I DONT KNOW ABOUT?? I PRETTYMUCHTHINK I KNOWABOUT ALMOST ALLOF THE AFTERMARKET PARTS THERE IS FOR THESE CARS BUT THIS ONE HAS ME GOIN CRAZY BECAUSEESPECIALLY THE 5.0 SHOOTOUT IS FRIDAY. ANY EXPERIENCED REPLYS IS GREATLY APPRETIATED. ITS BEEN ALONG TIME SINCE IHAVE BEEN ON THIS FRUM. THANX!

mdvaldosta

Wow that was hard to read. Never heard of an "internal" chip, although reflashing of the cpu without using a chip can be done. As far as a chip being used to override internal AFTERMARKET reflashing - I dunno Im not that experience with that aspect, although Im sure the tuner you've taken your car to should be.

89muscle

YEA SORRY MY SPACE BAR DOESNT WORK SOMETIMES. WELL THE CAR IS STILL AT THE DYNO PLACE AND HE SAID WITHOUT THE CHIP IT RUNS OK BUT NOT LIKE IT SHOULD. WHEN IT GOES INTO CLOSED LOOP, IT GOES NUTS.

mdvaldosta

As in, you don't have a chip and they can't reflash your ecu? Most all places that dyno tune only reflash an aftermarket chip - they should be able to tell you more than we can.

Oh, and I was referring to your caps lock

hunterzach_02

if you have figured anything out let me know. i have the same prob with mine. I was told that the stock fuel curve makes them run lean unless it is wot. since it is lean it backfires through the intake. i have a custom jet chip in mine and it still does it.