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Engine RPM cut out intermittently

  • Thread starter Thread starter RotFox90
  • Start date Start date May 5, 2024

RotFox90

Member
Jan 21, 2024
21
3
13
Connecticut
May 5, 2024
#1
  • May 5, 2024
  • #1
Hey All,

Curious to see if anyone else has experienced and knows the probable cause.

So as the title states, my RPM will drop intermittently after driving for a bit. You feel the car lose power as well. The car has had that problem since I bought it, I put on a replacement distributor and TFI from RockAuto and seemed to clear it up.

(I have the TFI remote mounting kit installed- these parts installed maybe a year ago, take it for a short drive maybe 1/2 times a week, sometimes sits a little longer-so not many miles on the parts, I know they can just be crap replacement parts) New fuel filter. New replacement MAF sensor as well from RockAuto.

It does happen more frequently when it’s warmer. No CEL/no stored codes. Distributor/TFI?
 

AeroCoupe

lube between the nut and the face. I know my lubes
Founding Member
Oct 28, 2001
5,870
3,992
183
Claremore, OK
May 5, 2024
#2
  • May 5, 2024
  • #2
Is the ECU original i.e. never been repaired? If so you may want to pull it and check the caps. They can be swollen and also have corrosion where the legs solder to the board. These computers are all over 30 years old now so the failure rate is rising rapidly. ECU Exchange is where most are sending them. Not saying this is the cause but it seems to be a trend.
 
Reactions: Mindseye007 and limp

RotFox90

Member
Jan 21, 2024
21
3
13
Connecticut
May 5, 2024
#3
  • May 5, 2024
  • #3
Great suggestion. I’ll definitely look into it. As far as I know, it’s original.
 

Mindseye007

10 years still blowing strong
5 Year Member
Oct 21, 2020
573
131
63
ontario
May 7, 2024
#4
  • May 7, 2024
  • #4
Mindseye007 said:
have you tried a smoke test? what TFI did you buy from Rockauto? also which TFI remote mounting kit? where did you mount it? and check your current TFI Module, by buying this off Ebay https://www.ebay.ca/itm/25553718100...pid=5335821607&customid=&toolid=10001&mkevt=1
and don't for get to buy a 9 Volt Battery.
just like Aero Coupe said, The ECU Exchange is the best place to get your ECU it fixed at. I had mine sent in and they repaired the 3 caps and it was done flawless.

1986-2004 Ford Mustang A9L A9P ECU Repair Service

1986-2004 Ford Mustang A9L A9P ECU Repair Service Engine Computer Repair Please fill out the R&R form here once you've placed your order.ORInclude a note in the box with your order number and vehicle symptoms.A Trusted Product with LIFETIME WARRANTY QUICK TURN AROUND TIMEDomestic and...
www.theecuexchange.com
hope this helps you solve the issue.
Click to expand...
 
Last edited: May 7, 2024

RotFox90

Member
Jan 21, 2024
21
3
13
Connecticut
May 9, 2024
#5
  • May 9, 2024
  • #5
That’s a cool little tool.

I don’t remember the brand off hand, I believe Standard Motor Products? Which from my experience usually has decent OE replacement parts.

I have it mounted on the passenger side of the engine bay along the fender.

How much can the ecu repair cost?
 

AeroCoupe

lube between the nut and the face. I know my lubes
Founding Member
Oct 28, 2001
5,870
3,992
183
Claremore, OK
May 9, 2024
#6
  • May 9, 2024
  • #6
$150

Ford Mustang 5.0 A9L A9P C3W A3M X3Z ECU Repair Service

Ford Mustang 5.0 A9L A9P C3W A3M X3Z ECUEngine Computer Repair ServicePlease fill out the R&R form here once you've placed your order.A Trusted Product with LIFETIME WARRANTY QUICK TURN AROUND TIMEDomestic and International Shipping available! Our Team is Available Monday - Friday 9am to 5pm...
www.theecuexchange.com
 
Reactions: Mindseye007

Mindseye007

10 years still blowing strong
5 Year Member
Oct 21, 2020
573
131
63
ontario
May 9, 2024
#7
  • May 9, 2024
  • #7
RotFox90 said:
That’s a cool little tool.

I don’t remember the brand off hand, I believe Standard Motor Products? Which from my experience usually has decent OE replacement parts.

I have it mounted on the passenger side of the engine bay along the fender.

How much can the ecu repair cost?
Click to expand...
Can you take a pic of it installed?
 

RotFox90

Member
Jan 21, 2024
21
3
13
Connecticut
Jun 1, 2024
#8
  • Jun 1, 2024
  • #8
Hey guys,

Sorry I forgot to answer. I’ll post a picture of it installed tomorrow.
 
Reactions: Mindseye007

RotFox90

Member
Jan 21, 2024
21
3
13
Connecticut
Jun 11, 2024
#9
  • Jun 11, 2024
  • #9
Here we are-right next to the MAF Sensor on the inner fender
RotFox90 said:
Hey guys,

Sorry I forgot to answer. I’ll post a picture of it installed tomorrow.
Click to expand...


 
Reactions: Mindseye007
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