OK LETS START WITH MY MODS. I HAVE UPR CAI/ MAGNFLOW X PIPES. STEEDA CAT BACKS. AND 3.0 RR PULLEY WITH GATES BELT. NO CHIP ONE ON THE WAY. WHEN I GIVE IT FULL THORTLE IN FIRST GEAR, HIT 5000 RPM THE CAR BOGS. AND MY RPM DROPS TO 2000 . THIS DOES NOT HAPPEN IF I SLOWLY APPLY THE GAS PEDEAL IT GOES RIGHT TO 6500 NO PROBLEM. ALSO IT DOES NOT OCCUR IN ANY OTHER GEAR. THE CAR WAS DYNO AT 440/338. WE HOOKED UP A AUTO TAP TO CHECK IT OUT. I WENT FROM 40POUNDS OF PRESSURE TO 10 POUNDS OF PRESSURE AT 5000RPM IN FIRST GEAR. AT HARD ACCELERATION:A/F IS FINE ON THE DYNO. ANY IDEAS. ANY ONE HAVE A SIMULAR PROB. I'AM NOT SURE A CHIP WOULD SLOVE THIS PROB.
MAJOR BOG AND LOSS OF GAS PRESSURE
- Thread starter Get Ready
- Start date
Is your traction control on??
A 3" pulley CAI and no chip? I'd like to see that dyno graph.
If your fuel pressure is dropping that drastically, you might want to think about not going WOT. Sounds to me like a disaster waiting to happen.
Has the computer thrown any codes?
Any other problems like hard starts??
A 3" pulley CAI and no chip? I'd like to see that dyno graph.
If your fuel pressure is dropping that drastically, you might want to think about not going WOT. Sounds to me like a disaster waiting to happen.
Has the computer thrown any codes?
Any other problems like hard starts??
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NO HARD STARTS .ILL TRY TO POST THE DYNO GRAPH. NO CODES ON THE COMPUTER
ONE OTHER THING IF I GIVE FULL THROTLE FROM A ROLL ITS FINE. TRACTION CONTROL OFF. HAVING DIFFICULT TIME POSTING THE GRAPH
wait to get the chip before you go wot
What chip will you be getting? 40psi fuel is too low for the 3" pulley. The stock A/F ratio is very lean at low/mid RPMs. You need at lesst 50psi at idle and 70psi fuel pressure at WPT with "NO DROP-OFF".
AMB
AMB
How many miles on your fuel filter??? Could be clogged! Good luck!
Bad FPS??
Sounds like you have a bad FPS. I am running the 2.93 with no chip and have no issues going to redline.
A little more info:
When the engine "bogs" it actually feels as though you have run up against the rev limiter.
We swapped out the fuel pressure sensor with a new one and there was no change.
We disconnected the boost by-pass and no change.
There was one code thrown:
P0234 - Supercharger Overboost Condition
The PCM disables (bypasses) the supercharger boost and sets a diagnostic trouble code (DTC) to keep from damaging the powertrain (engine or transmission) during potential harmful operating conditions.
· Brake torque (brake on and throttle at wide open) · Transmission oil temperature (TOT) exceeds calibrated threshold ·
Engine over temperature ·
Ignition misfire exceeds calibrated threshold · Knock sensor (KS) failure or knock detected ·
Low speed fuel pump relay not switching
From reading the data from the AutoTap, it would appear that the PCM is shutting off the fuel pressure for some reason.
Pressure is fine up about 5000 RPM's then just drops off to less than 10 psi. I don't know if the drop in pressure is a cause or an effect of the engine speed dropping off. But I would have to guess it is causing it.
The unusual thing is that if you start from a roll, it is fine. If you start from a stop, or only a few miles per hour, the problem occurs.
The car has about 5000 and has the original fuel filter.
It also does not do it in any gear but first gear.
Does anyone have any info on what the "low speed relay" is that is referenced above? or if it applies to this car?
The problem existed before the 3 inch pulley was installed, but became much more obvious then.
Dana
When the engine "bogs" it actually feels as though you have run up against the rev limiter.
We swapped out the fuel pressure sensor with a new one and there was no change.
We disconnected the boost by-pass and no change.
There was one code thrown:
P0234 - Supercharger Overboost Condition
The PCM disables (bypasses) the supercharger boost and sets a diagnostic trouble code (DTC) to keep from damaging the powertrain (engine or transmission) during potential harmful operating conditions.
· Brake torque (brake on and throttle at wide open) · Transmission oil temperature (TOT) exceeds calibrated threshold ·
Engine over temperature ·
Ignition misfire exceeds calibrated threshold · Knock sensor (KS) failure or knock detected ·
Low speed fuel pump relay not switching
From reading the data from the AutoTap, it would appear that the PCM is shutting off the fuel pressure for some reason.
Pressure is fine up about 5000 RPM's then just drops off to less than 10 psi. I don't know if the drop in pressure is a cause or an effect of the engine speed dropping off. But I would have to guess it is causing it.
The unusual thing is that if you start from a roll, it is fine. If you start from a stop, or only a few miles per hour, the problem occurs.
The car has about 5000 and has the original fuel filter.
It also does not do it in any gear but first gear.
Does anyone have any info on what the "low speed relay" is that is referenced above? or if it applies to this car?
The problem existed before the 3 inch pulley was installed, but became much more obvious then.
Dana
iI JUST GOT OF THE PHONE WITH RICK THE CHIP WILL NOT CORRECT THE PROBLEM, HE FEELS IT MIGHT ME THE FUEL FILTER, OR THE FUEL RAIL SENSOR. AND THERE HAS BEEN SIMILIAR PROBLEMS IN SOME LIGHTINGS, AND IT WAS A LOSE FUEL PICK UP LINE IN THE TANK. ANY OTHER IDEAS WOULD BE APPRECIATED.
Get Ready, could you turn caps lock off 
Ok.. I'am in withdraws
Could be underachieving fuel pumps too.
Dan,
You need to call me ASAP. I have some information for you.
MJ
sounds like the timing is dropping because of a dangerous cylinder condition....get a chip
I just recivied the chip from amazon. I will change the gas filter.. check the fuel rail sensor. And make a decision on the chip. Try to keep warranty. May have to remove a few Items. Just my luck it will run fine. After I remove a few things.
it totally sounds like somebody forgot to turn off the traction control
only happens in first is a dead giveaway
only happens in first is a dead giveaway
Well it could really be just the Fuel Pump. We saw one go bad this weekend....just like that. He pulled to the shop with no problems. Moved the car else were. We wanted to do a battle between the Magna-Paks & Stingers....but the car just died. Would not start at all again.
Checked the FPS...that was good.
Checked the Fuel Presure...that was good also.
Ran it on a pretty good OBII scanner to check every thing & no signs of trouble.
Shop checked all the fuses just in case & we found 1 fuse to keep blowing bad....it was the fuel pump.
Might want to check into that as well :shrug: IMO.
Checked the FPS...that was good.
Checked the Fuel Presure...that was good also.
Ran it on a pretty good OBII scanner to check every thing & no signs of trouble.
Shop checked all the fuses just in case & we found 1 fuse to keep blowing bad....it was the fuel pump.
Might want to check into that as well :shrug: IMO.
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