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I'm Sill Alive! Very Strange Dyno Results Inside

  • Thread starter Thread starter red94fiveo
  • Start date Start date Jul 16, 2004

red94fiveo

New Member
Apr 12, 2003
1,269
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0
Wichita, KS
Jul 16, 2004
#1
  • Jul 16, 2004
  • #1
Yes, I realize I haven't posted here in about 2 months, but I am still alive. Starting a new job and moving at the same time makes it kinda hard to post on stangnet, but anyway I'm back.

Here has been the timeline on my car this year. Got the H/C/I done in april and it ran like an SOB at WOT, but it wouldn't idle worth a s***. So I ordered a JMS chip in may to try and get everything taken care of. I have had problems ever since I installed the chip. The car idles now but doesn't run worth a s*** WOT. I got m car dynoe'd last night and found out why.

Attached are my last two dyno runs. We made 6 attempts but never could make a complete run. My A/F would ok up until about 3500-4000 RPM, and then it would ge really really lean in a hurry! I'm talking like above 18-20:1 lean! We had to shut down pretty quickly each time. (Fuel Pressure was at 43 w/ vac removed and timing at 10* for all the runs). The second dyno run attached is with the chip off, but I don't think the computer had time to reset, since it did the same thing on the dyno and acted like it had the chip in when I drove it home after that (still idling, but running like crap). I drove the car this morning and it seems like the computer is starting to reset itsself. It now won't idle at all (like before) and runs better at WOT. It now doesn't go really lean until about 4800-5000 and that number is getting higher the more I drive the car. Suggestions?

I'm going to call JMS Monday (couldn't get a hold of them today) and ask for my money back. This chip has been ****ty from the start. I'm going to go drive up to KC and get a chip burned on the dyno.

Its good to be back!

*OK, the dyno charts are in a PDF and I can't get them uploaded. If someone can host a 512K file I would appreciate it.

Here what the dyno looks like:

with chip:
smooth until 3600, 220HP, 300TQ, then it gets real bumpy and drops, this is where we shut down b/c of the sever elan condition

without chip immediately after:
same as above, except 229HP and 311TQ b/f shutdown at about 3900.
 

Grn92LX

Fidanza Man!
Founding Member
Jan 14, 2001
6,819
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129
New York
Jul 16, 2004
#2
  • Jul 16, 2004
  • #2
What injectors? The chip tune should help dial the car in. If not, maybe they can diagnos why it's running lean. Bad pump, bad maf or a clogged filter come to mind. Your car just may not like the c&l. Post your reesults when you get them!
 

red94fiveo

New Member
Apr 12, 2003
1,269
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0
Wichita, KS
Jul 16, 2004
#3
  • Jul 16, 2004
  • #3
Grn92LX said:
What injectors? The chip tune should help dial the car in. If not, maybe they can diagnos why it's running lean. Bad pump, bad maf or a clogged filter come to mind. Your car just may not like the c&l. Post your reesults when you get them!
Click to expand...

24# injectors, C&L cal'd for them, new 76mm C&L MAF, and new 255 Walbro FP, fuel delivery shoudn't be a problem for me. And the car ran great at WOT with the H/C/I done before I put the chip on, with none of this lean s**.
 

GTJake

Founding Member
Oct 28, 2002
3,049
0
56
Ann Arbor, MI
Jul 16, 2004
#4
  • Jul 16, 2004
  • #4
I can host them. Opps...didn't see they were PDF, sorry.

Jake
 

Grn92LX

Fidanza Man!
Founding Member
Jan 14, 2001
6,819
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129
New York
Jul 16, 2004
#5
  • Jul 16, 2004
  • #5
red94fiveo said:
24# injectors, C&L cal'd for them, new 76mm C&L MAF, and new 255 Walbro FP, fuel delivery shoudn't be a problem for me. And the car ran great at WOT with the H/C/I done before I put the chip on, with none of this lean s**.
Click to expand...


Typical case of what I call a "gay eec" Sometimes you make changes and the eec doesnt adapt like it should and you go through this running lean BS. For example- I ran a full trickflow combo with a 76mm c&l maf. A/F was dead on perfect, I tuned it myself. A year or so later I made some combo changes, Longtube headers, had the heads milled .020" and an FTI custom grind cam. The car was now very lean on the dyno. Most people can get by with 24lb inejctors with that combo, but not me and my friend. We both needed 30's The chip should fix your issues definatly.
 

red94fiveo

New Member
Apr 12, 2003
1,269
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0
Wichita, KS
Jul 17, 2004
#6
  • Jul 17, 2004
  • #6
Grn92LX said:
Typical case of what I call a "gay eec" Sometimes you make changes and the eec doesnt adapt like it should and you go through this running lean BS. For example- I ran a full trickflow combo with a 76mm c&l maf. A/F was dead on perfect, I tuned it myself. A year or so later I made some combo changes, Longtube headers, had the heads milled .020" and an FTI custom grind cam. The car was now very lean on the dyno. Most people can get by with 24lb inejctors with that combo, but not me and my friend. We both needed 30's The chip should fix your issues definatly.
Click to expand...

The chip has been my problem. Like I said, before the chip the car ran great at WOT, even though it wouldn't idle. After the chipo went on the car idled better, but then this lean s*** started.
 

Grn92LX

Fidanza Man!
Founding Member
Jan 14, 2001
6,819
64
129
New York
Jul 17, 2004
#7
  • Jul 17, 2004
  • #7
I know that, thats why you dont take the hit or miss chance with mail order custom chips. Want a chip, then you have to have a dyno tuned one done. That should fix your lean issue. Have you tried disconnecting the battery overnight to clear out the KAM and trying again?
 

red94fiveo

New Member
Apr 12, 2003
1,269
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0
Wichita, KS
Jul 17, 2004
#8
  • Jul 17, 2004
  • #8
Grn92LX said:
I know that, thats why you dont take the hit or miss chance with mail order custom chips. Want a chip, then you have to have a dyno tuned one done. That should fix your lean issue. Have you tried disconnecting the battery overnight to clear out the KAM and trying again?
Click to expand...

Yeah, I really should have listened to everyone and got a dyno tuned one, which it looks like it will end up doing anyway. (Unfortunately the closest place to me that will do it is three hours away!) Will they still be able to fix my problem or is my PCM fried or something? Also, how long does the battery need to be unplugged to clear the KAM out? I unplugged it for like an hour yesterday, but i'll probably unplug it for the whole night tonight, thanks for the suggestions.
 

Grn92LX

Fidanza Man!
Founding Member
Jan 14, 2001
6,819
64
129
New York
Jul 17, 2004
#9
  • Jul 17, 2004
  • #9
Your comp is fine, its the chip thats not tuned right. Thats why you need a dyno tuned one. Most pro-tuners prefer pro-m's over c&l whens doing chip tunes.

I disconnected my battery overnight once and that helped out a lot.
 

Paul Perreca

New Member
Mar 30, 2005
1,085
0
0
Mar 24, 2006
#10
  • Mar 24, 2006
  • #10
I had JD's Performance custom burn me a chip - now the car runs like a sob n idles like a mother too! lol
 

Killercanary

The car that set the bar.
Founding Member
Nov 29, 1999
5,676
1
76
Altoona, PA
Mar 24, 2006
#11
  • Mar 24, 2006
  • #11
Holy old thread!


This OLD thread was the first time I have heard anything negative about a JMS chip.

JD's is now doing chips?!?!
 

mytight95

Active Member
Apr 11, 2003
2,605
0
46
Dothan,Al
Mar 24, 2006
#12
  • Mar 24, 2006
  • #12
i had the same issues with my JMS chip Paul......


jason
 

SeventyMach1

Keep it lubed .... keep it straight .... and keep
Mar 30, 2005
1,940
3
36
North Carolina
Mar 24, 2006
#13
  • Mar 24, 2006
  • #13
Sounds like all the money spent toward "guessing" with a chip .... he could have just bought a self tuner and called it a day.


220HP with H/C/I & bolt-ons doesn't sound too fun.
 
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