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cutting out at 4k and up!!!

  • Thread starter Thread starter Mr. Rustypwnz
  • Start date Start date Jun 17, 2007

Mr. Rustypwnz

Advanced Member
Jun 1, 2005
1,761
63
69
indianapolis/ valdosta ga
Jun 17, 2007
#1
  • Jun 17, 2007
  • #1
yo, first of all my 86gt, has gt40p heads, tmoss intake and a b cam, 65mmtb and a full exhaust with a 255lph pump and other little things. Anyway it was running great the other day so I went and filled it up at an inland station, long story short, there gas is mixed with like 20% or 10% something like that, well I take it out for a drive and it starts knocking and idling at like 2k!!! Has no power and is getting hot, well I smoked a plugwire, and the idle motor is stuck open, so no big deal, I put another plug on and unplug it, and turn the timing 2 deg's back, I drive it today and it runs great up to about wot, but once you put it down it starts cutting out, no knocking just this loud BLAHHHHHDDDDD deep throatty sound and no go, it actually gets slower and keeps busting up, I mean I can floor it from 1500 and it will pull from hell to 4k and then start this like "pop" then it pulls like hell for a second then will do it again and then pull to redline for a sec then I shift and it starts over again!! It feels like a small vac leak, but I cant find any!! HELP SAVE MY STANG!!!

Josh
 

jrichker

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Jun 17, 2007
#2
  • Jun 17, 2007
  • #2
TFI module failure mode is loss of spark at high RPM and a warm engine. Does this sound like what's happening to you?

If not, then...

Dump the codes and see what the computer says is wrong…Codes may be present in the computer even if the Check Engine light isn’t on.

Here's the link to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great.

See http://www.troublecodes.net/Ford/







IF your car is an 86-88 stang, you'll have to use the test lamp or voltmeter method. There is no functional check engine light on the 86-88's except possibly the Cali Mass Air cars.

Codes have different answers if the engine is running from the answers that it has when the engine isn't running. It helps a lot to know if you had the engine running when you ran the test.

Trouble codes are either 2 digit or 3 digit, there are no cars that use both 2 digit codes and 3 digit codes.

For those who are intimidated by all the wires & connections, see http://www.actron.com/product_detail.php?pid=16153 for what a typical hand scanner looks like. Normal retail price is about $30 or so at AutoZone or Wal-Mart.

Or for a nicer scanner see http://www.midwayautosupply.com/pc-7208-90-equus-digital-ford-code-reader-3145.aspx – It has a 3 digit LCD display so that you don’t have to count flashes or beeps.. Cost is $30.
 

Mr. Rustypwnz

Advanced Member
Jun 1, 2005
1,761
63
69
indianapolis/ valdosta ga
Jun 17, 2007
#3
  • Jun 17, 2007
  • #3
yeah ill try that, ill swap one on tomorrow, and see whats wrong, It only does it only when warm as well, so I guess i found the problem!! Does any parts store check these?
 

jrichker

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Jun 18, 2007
#4
  • Jun 18, 2007
  • #4
slow95gt said:
yeah ill try that, ill swap one on tomorrow, and see whats wrong, It only does it only when warm as well, so I guess i found the problem!! Does any parts store check these?
Click to expand...

Many auto parts stores will check them. Bring along a hair dryer to heat the module while it is being tested. The modles tend to fail most when they get hot.

When replacing the module, clean the old heat sink compound off and use some fresh compound. If the auto parts store does not have heat sink compound , Radio Shack will.
 
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