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Help me figure out this ongoing issue:

  • Thread starter Thread starter reeber
  • Start date Start date Aug 24, 2005

reeber

10 Year Member
Mar 10, 2004
574
26
38
Berlin, NJ
Aug 24, 2005
#1
  • Aug 24, 2005
  • #1
1. As I am cruising, I let off the gas and the car stays on the gas for about a 3 count, then drops.

2. If I hit the brake hard, the car stalls, or almost stalls then jumps up to 1,200 RPM.

3. When car is cool (not cold), idle is all over the place from 1,500 RPM, down to 500 RPM. When at operating temperature, still hunts for idle, but not as bad as it is when cold.

We swapped the MAF and the car did the same thing. So, it's not that. We know our MAF is not the problem. We replaced the IAC as well. It does the same thing the old one did. We tried the IAC restricter plate. That didn't work. We played with the tune and made it better, but still extremely annoying. Anyone else have ideas on what to check?

Do you think it could be the EEC? It runs awesome at WOT and part throttle, but can't idle worth of crap.
 

stangman

15 Year Member
Jul 10, 2003
2,690
10
69
in a 3 bed, 2 bath
Aug 24, 2005
#2
  • Aug 24, 2005
  • #2
reeber said:
1. As I am cruising, I let off the gas and the car stays on the gas for about a 3 count, then drops.

2. If I hit the brake hard, the car stalls, or almost stalls then jumps up to 1,200 RPM.

3. When car is cool (not cold), idle is all over the place from 1,500 RPM, down to 500 RPM. When at operating temperature, still hunts for idle, but not as bad as it is when cold.

We swapped the MAF and the car did the same thing. So, it's not that. We know our MAF is not the problem. We replaced the IAC as well. It does the same thing the old one did. We tried the IAC restricter plate. That didn't work. We played with the tune and made it better, but still extremely annoying. Anyone else have ideas on what to check?

Do you think it could be the EEC? It runs awesome at WOT and part throttle, but can't idle worth of crap.
Click to expand...



sounds to me like the car was tuned for WOT & that's it. as far as the gas pedal....do you have after market floor mats or is yours kinds clumped up near the pedal?
 

jstreet0204

Active Member
Jun 26, 2003
939
0
36
Winston Salem, NC
Aug 24, 2005
#3
  • Aug 24, 2005
  • #3
I think I have mentioned this in one of your other threads, but you really need to do some dataloging to track this down. You have so many mods it could be a multitude of things. It is likely o2 related, and possibly cooling off during closed throttle, because of the long tubes. Header wrap on the collectors may help, but without datalogs, it is a shot in the dark.
 

reeber

10 Year Member
Mar 10, 2004
574
26
38
Berlin, NJ
Aug 24, 2005
#4
  • Aug 24, 2005
  • #4
jstreet0204 said:
I think I have mentioned this in one of your other threads, but you really need to do some dataloging to track this down. You have so many mods it could be a multitude of things. It is likely o2 related, and possibly cooling off during closed throttle, because of the long tubes. Header wrap on the collectors may help, but without datalogs, it is a shot in the dark.
Click to expand...

We did some data logging with the Predator and the biggest problem we run into is the loads. The loads are all over the place, even at WOT. Chris from DiabloSport was the tuner and he was getting just as frustrated as all of us. My long tubes are ceramic coated. We did not check the O2 sensors.
 

reeber

10 Year Member
Mar 10, 2004
574
26
38
Berlin, NJ
Aug 24, 2005
#5
  • Aug 24, 2005
  • #5
stangman said:
sounds to me like the car was tuned for WOT & that's it. as far as the gas pedal....do you have after market floor mats or is yours kinds clumped up near the pedal?
Click to expand...

I don't have floor mats.
 
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