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Help! I think I have detonation. :(

  • Thread starter Thread starter 02LaserRed2V
  • Start date Start date Sep 12, 2004

02LaserRed2V

New Member
Jul 30, 2004
379
1
0
Augusta, GA
Sep 12, 2004
#1
  • Sep 12, 2004
  • #1
1.) First thing's first: The SES light came on ever since I had my Diablosport chip installed.

2.) My car seems to be running rich now. Gas mileage is gotten noticeably worse. The exhaust now emits a stronger odor as if the gas isn't burnt.

3.) I've lost some power as well. For a while, I thought I was simply getting used to the power, but I now know for a fact my car isn't performing to its potential. And I sometimes hear a rattling (that infamous marbles in a tin can sound) when I accelerate up an incline.

I originally thought an exhaust leak was the cause. But after reading topics on detonation, I'm starting to believe the latter is my problem (to my dismay). Something tells me the chip is causing this. I suppose now's a good time to get the codes read? What do you guys think? Much of this tech stuff is still new to me so any word or advice would be much appreciated.
 

twogts4us

15 Year Member
Apr 1, 2004
4,188
12
79
Dunedin, FL
Sep 12, 2004
#2
  • Sep 12, 2004
  • #2
Well, if you you had it installed by someone else, I'd take it back.
Detonation is a sign of running lean or too much spark advance (or both).
First thing I'd do is remove the chip, clean the contacts of the computer port(with a scotchbrite pad) and then reinstall.
 

wms004

Founding Member
Jan 15, 2002
2,864
2
49
Los Angeles
Sep 12, 2004
#3
  • Sep 12, 2004
  • #3
one sure fix-- dynotune
 

02LaserRed2V

New Member
Jul 30, 2004
379
1
0
Augusta, GA
Sep 12, 2004
#4
  • Sep 12, 2004
  • #4
I've gotten the chip online (Partshopper). I kinda gambled on that, hoping the chip would be tuned properly on the first try. Anyhow, I've just found out there is a diablosport dealer located in my area, so I suppose they can work on it.

Also, I hear dyno tunes can cost around $500-$600? That'll make my wallet quite thin, but I'm now at the point where I'm willing to pay that much if that's the only or last option to get my car running right again.
 

twogts4us

15 Year Member
Apr 1, 2004
4,188
12
79
Dunedin, FL
Sep 12, 2004
#5
  • Sep 12, 2004
  • #5
A dyno tune is the best answer, but it's really not necessary. So you're saying you bought a brand new chip and it's making your car behave like you've described? Send it back and have them fix it (tell them you also need a loaner chip in the meantime to keep your trannie shifting properly with the 4.10s) It pays to bitch!
But first, I'd clean the contacts of the computer port - they must be VERY clean - you'd be surprised how often this is the problem with newly installed chips. You've got to clean it all the way down to the brass contacts.
 

wms004

Founding Member
Jan 15, 2002
2,864
2
49
Los Angeles
Sep 12, 2004
#6
  • Sep 12, 2004
  • #6
02LaserRed2V said:
I've gotten the chip online (Partshopper). I kinda gambled on that, hoping the chip would be tuned properly on the first try. Anyhow, I've just found out there is a diablosport dealer located in my area, so I suppose they can work on it.

Also, I hear dyno tunes can cost around $500-$600? That'll make my wallet quite thin, but I'm now at the point where I'm willing to pay that much if that's the only or last option to get my car running right again.
Click to expand...
5-600 includes the chip. Can they tune that kind of chip you already have.. cuz that would be only about 75 an hour for tuning, which takes about an hour.
 

02LaserRed2V

New Member
Jul 30, 2004
379
1
0
Augusta, GA
Sep 13, 2004
#7
  • Sep 13, 2004
  • #7
Well, first thing's first, I've gotten the codes/diagnostics checked. Two faults showed up:

P0605 (Ensure aftermarket performance products are not installed before replacing PCM Replace PCM)

P1639 (Flash Vehicle Identification Block needs to be reprogrammed)


The faulty PCM seems to be the culprit.
 
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