Ford Ranger Forum - Forums for Ford Ranger enthusiasts!

Go Back   Ford Ranger Forum - Forums for Ford Ranger enthusiasts! > > >
Forgot Password? Join Us!

Welcome to Ford Ranger Forum

Reply
 
Thread Tools Search this Thread

  #1  
Old 10-13-2012, 05:23 PM
Sub74 Sub74 is offline
Sub74
 
Join Date: Mar 2012
Posts: 512
Default Eating computers - getting expensive

My 88 2.9L is killing a computer every 4 - 6 weeks.
Runs great when it does run, except for the very low oil pressure

Any brilliant ideas as to why it keeps having this same problem?

By the way when I do the KOEO test I get a different fault each time. No consistency to it.

The KOEO is always code 11 after the initial test but when I install the new computer it starts & runs fine
__________________
1988 Ranger STX, custom built flatbed, winch, 33x 10.5 BFG mudders
1974 Suburban (AKA "the sub") lockers front & rear, 383 cu in not even close to stock motor, snowplow 37 x 12.5 HUMMV tires, 4.56 gears
1952 M38 (CJ3) Jeep - my newest project - 289 ford, hardtop, got it with not one wire in it. Hope to have it driving this year
Reply With Quote
  #2  
Old 10-13-2012, 06:24 PM
FireRanger FireRanger is offline
Blinded by the light
 
Join Date: Sep 2009
Posts: 7,674
Send a message via AIM to FireRanger
Default Re: Eating computers - getting expensive

Any of the wires going to any of the many sensors, or any of the power wires, has an ugly fault on it. Have fun tracing every piece of wire to find it...
__________________
(Formerly)
FireRanger
2003 Edge 4.0 4wd

How to: Aux light wiring, relays, & fuses
Info: 300+ intake threads here on FRF
Info: HID Projectors
How To: NO HEAT Troubleshooting Guide
Reply With Quote
  #3  
Old 10-13-2012, 08:36 PM
Sub74 Sub74 is offline
Sub74
 
Join Date: Mar 2012
Posts: 512
Default

Trying to avoid that, hoping someone can point me to a smaller area than the whole engine wiring harness.
Probably can't, but I can always hope
__________________
1988 Ranger STX, custom built flatbed, winch, 33x 10.5 BFG mudders
1974 Suburban (AKA "the sub") lockers front & rear, 383 cu in not even close to stock motor, snowplow 37 x 12.5 HUMMV tires, 4.56 gears
1952 M38 (CJ3) Jeep - my newest project - 289 ford, hardtop, got it with not one wire in it. Hope to have it driving this year
Reply With Quote
  #4  
Old 10-13-2012, 09:51 PM
Rangerman49 Rangerman49 is offline
If it works,don't fix it!
 
Join Date: Dec 2011
Posts: 966
Default Re: Eating computers - getting expensive

Quote:
Originally Posted by Sub74 View Post
Trying to avoid that, hoping someone can point me to a smaller area than the whole engine wiring harness.
Probably can't, but I can always hope

I have heard that a alternator with a bad output, ie. noise riding on the DC output (Static) will cause the ECM to fail. The cause is a breakdown of a diode in bridge rectifier that converts the AC output to DC that is the output of the alternator. The only way to see if this the case ,is to hook up a oscilloscope and look at the waveform. Most automotive electric shops have a tester that does the same thing.
__________________
2011 Ranger XLT 2x4,4.0 SOHC, 5 Speed Auto, 3.55 Rear. Oxford White.

Simplicity is the ultimate sophistication.

Torque it down till it breaks off, then back it off 1/4 turn.
Reply With Quote
  #5  
Old 10-13-2012, 10:24 PM
Sub74 Sub74 is offline
Sub74
 
Join Date: Mar 2012
Posts: 512
Default

That sounds reasonable & alternators are cheap & easy to install, guess I'll start there
__________________
1988 Ranger STX, custom built flatbed, winch, 33x 10.5 BFG mudders
1974 Suburban (AKA "the sub") lockers front & rear, 383 cu in not even close to stock motor, snowplow 37 x 12.5 HUMMV tires, 4.56 gears
1952 M38 (CJ3) Jeep - my newest project - 289 ford, hardtop, got it with not one wire in it. Hope to have it driving this year
Reply With Quote
  #6  
Old 10-13-2012, 10:28 PM
FireRanger FireRanger is offline
Blinded by the light
 
Join Date: Sep 2009
Posts: 7,674
Send a message via AIM to FireRanger
Default Re: Eating computers - getting expensive

Ahhhh. I can't believe I didn't think of that. I knew there was something else and my brain is just melting with work.

If you alternator's voltage regulator is shot, it can be sending spikes that will fry the computer in an instant. These systems are pretty forgiving up to about 16 volts. After that, things start to cook.

I would replace the alternator. It is nearly impossible to test for an intermittent problem. You could sit there all day with a meter and it might never happen. Then next time you drive, poof. So you're kinda replacing it hoping it is the problem. Compared to the cost of more new computers and the time tracing about a mile of wire, it is probably worth a shot.
__________________
(Formerly)
FireRanger
2003 Edge 4.0 4wd

How to: Aux light wiring, relays, & fuses
Info: 300+ intake threads here on FRF
Info: HID Projectors
How To: NO HEAT Troubleshooting Guide
Reply With Quote
  #7  
Old 10-14-2012, 09:31 AM
Rangerman49 Rangerman49 is offline
If it works,don't fix it!
 
Join Date: Dec 2011
Posts: 966
Default Re: Eating computers - getting expensive

Quote:
Originally Posted by Sub74 View Post
That sounds reasonable & alternators are cheap & easy to install, guess I'll start there
I would also clean and all the grounds you can find, that may dampen some of any leftover noise to ground, like a electronic shock absorber..
Just as an example , a friend of mine wife had left the lights on his Dodge while she was in a store, he came out and jump it ,got home and put it on his Granddads old shop charger that he got when he closed the shop and retired. Fast forward to next morning, Cars completely dead and has it towed to the dealer because it was under warranty. They found that every control module was fried because of the charger. Seems that old school chargers from the 60's were not pure DC output, but that didn't matter on cars of that time.
So be careful what chargers you use too!!!
__________________
2011 Ranger XLT 2x4,4.0 SOHC, 5 Speed Auto, 3.55 Rear. Oxford White.

Simplicity is the ultimate sophistication.

Torque it down till it breaks off, then back it off 1/4 turn.
Reply With Quote
  #8  
Old 10-14-2012, 03:37 PM
Sub74 Sub74 is offline
Sub74
 
Join Date: Mar 2012
Posts: 512
Default

Just recently re-did all the grounds because of a completely different problem.

I'll replace the alternator when I install the new computer. Takes a week to get a new computer.

The alternator is the one that came with the truck when I bought it 5-6 years ago, hard telling how old it really is.

This truck has been nothing but one headache after another for the past year.
__________________
1988 Ranger STX, custom built flatbed, winch, 33x 10.5 BFG mudders
1974 Suburban (AKA "the sub") lockers front & rear, 383 cu in not even close to stock motor, snowplow 37 x 12.5 HUMMV tires, 4.56 gears
1952 M38 (CJ3) Jeep - my newest project - 289 ford, hardtop, got it with not one wire in it. Hope to have it driving this year
Reply With Quote
  #9  
Old 10-23-2012, 10:29 PM
Sub74 Sub74 is offline
Sub74
 
Join Date: Mar 2012
Posts: 512
Default

OK finally got the new computer, installed it and the new alternator
Still won't start
Will run with fuel sprayed in the intake
Did a KOEO test, got codes 22 & 54 & 53
22 is the map sensor, unplugged it, still won't start
54 is the AIC - it is new one month ago
53 is ...?
has 38 psi fuel pressure
Has good spark
NOID light tests OK
Almost EVERYTHING is new about 1 month ago ie...
TPI
VAT
AIC
Both fuel pumps
MAP
All 6 injectors

OK give me your brilliant ideas

I'm about ready to junk this thing it has been more trouble than it is worth for the last year
__________________
1988 Ranger STX, custom built flatbed, winch, 33x 10.5 BFG mudders
1974 Suburban (AKA "the sub") lockers front & rear, 383 cu in not even close to stock motor, snowplow 37 x 12.5 HUMMV tires, 4.56 gears
1952 M38 (CJ3) Jeep - my newest project - 289 ford, hardtop, got it with not one wire in it. Hope to have it driving this year
Reply With Quote
  #10  
Old 10-24-2012, 09:53 AM
Rangerman49 Rangerman49 is offline
If it works,don't fix it!
 
Join Date: Dec 2011
Posts: 966
Default Re: Eating computers - getting expensive

Quote:
Originally Posted by Sub74 View Post
OK finally got the new computer, installed it and the new alternator
Still won't start
Will run with fuel sprayed in the intake
Did a KOEO test, got codes 22 & 54 & 53
22 is the map sensor, unplugged it, still won't start
54 is the AIC - it is new one month ago
53 is ...?
has 38 psi fuel pressure
Has good spark
NOID light tests OK
Almost EVERYTHING is new about 1 month ago ie...
TPI
VAT
AIC
Both fuel pumps
MAP
All 6 injectors

OK give me your brilliant ideas

I'm about ready to junk this thing it has been more trouble than it is worth for the last year

Code 53 is saying the TPS voltage is too high. Did you set it properly when installing the new one? If you did, it obviously has a problem and I would replace it with a new one meant for your year model, all TPS sensors are not the same.
This could be the reason for the no start..Wait for others to chime it..
Code 54 ACT sensor out of range. Broken or damaged wiring, bad ACT sensor. Note that that if the outside air temp is below 50 degrees F that the test for the ACT can be in error.
__________________
2011 Ranger XLT 2x4,4.0 SOHC, 5 Speed Auto, 3.55 Rear. Oxford White.

Simplicity is the ultimate sophistication.

Torque it down till it breaks off, then back it off 1/4 turn.
Reply With Quote
  #11  
Old 10-24-2012, 01:22 PM
Sub74 Sub74 is offline
Sub74
 
Join Date: Mar 2012
Posts: 512
Default

It was definitely below 50 degrees when I did the test, probably low 40's
__________________
1988 Ranger STX, custom built flatbed, winch, 33x 10.5 BFG mudders
1974 Suburban (AKA "the sub") lockers front & rear, 383 cu in not even close to stock motor, snowplow 37 x 12.5 HUMMV tires, 4.56 gears
1952 M38 (CJ3) Jeep - my newest project - 289 ford, hardtop, got it with not one wire in it. Hope to have it driving this year
Reply With Quote
  #12  
Old 10-24-2012, 01:43 PM
Doctor Wily Doctor Wily is offline
Science!
 
Join Date: Feb 2011
Posts: 369
Default Re: Eating computers - getting expensive

if the TPS sensor is reading higher than it should be, couldn't that put it in clear flood mode depending on how high the reading is?
__________________
Current: 2000 Ford Explorer XLS 4x4 Automatic 4.0L SOHC

Gone but not forgotten ~ "Ghetto Blue" my 1994 Mazda B2300 5 Speed Standard Cab 4x2.
Reply With Quote
  #13  
Old 10-24-2012, 06:23 PM
Rangerman49 Rangerman49 is offline
If it works,don't fix it!
 
Join Date: Dec 2011
Posts: 966
Default Re: Eating computers - getting expensive

Quote:
Originally Posted by Doctor Wily View Post
if the TPS sensor is reading higher than it should be, couldn't that put it in clear flood mode depending on how high the reading is?

That might enplane the no start until he sprays fuel in the intake, injectors are off....
__________________
2011 Ranger XLT 2x4,4.0 SOHC, 5 Speed Auto, 3.55 Rear. Oxford White.

Simplicity is the ultimate sophistication.

Torque it down till it breaks off, then back it off 1/4 turn.
Reply With Quote
  #14  
Old 10-24-2012, 07:00 PM
Doctor Wily Doctor Wily is offline
Science!
 
Join Date: Feb 2011
Posts: 369
Default Re: Eating computers - getting expensive

Quote:
Originally Posted by Rangerman49 View Post
That might enplane the no start until he sprays fuel in the intake, injectors are off....
My thoughts exactly :-D
__________________
Current: 2000 Ford Explorer XLS 4x4 Automatic 4.0L SOHC

Gone but not forgotten ~ "Ghetto Blue" my 1994 Mazda B2300 5 Speed Standard Cab 4x2.
Reply With Quote
  #15  
Old 10-24-2012, 10:02 PM
Sub74 Sub74 is offline
Sub74
 
Join Date: Mar 2012
Posts: 512
Default

The injectors are firing according to the fuel pressure and the NOID light
__________________
1988 Ranger STX, custom built flatbed, winch, 33x 10.5 BFG mudders
1974 Suburban (AKA "the sub") lockers front & rear, 383 cu in not even close to stock motor, snowplow 37 x 12.5 HUMMV tires, 4.56 gears
1952 M38 (CJ3) Jeep - my newest project - 289 ford, hardtop, got it with not one wire in it. Hope to have it driving this year
Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
most expensive video games Rango88 Music/Movies/Computers/etc. 2 07-12-2012 09:20 AM
Mac Computers Eagle Music/Movies/Computers/etc. 5 01-11-2012 11:28 AM
Craigslist / eBay Find: 07 FX4. Seems really expensive ZCrazy Trucks 12 08-07-2011 05:50 AM
Computers and Keys Oh My Leah Benner General Tech 8 07-16-2010 08:47 PM
Ford to save $1.2M year just by turning off its computers at night Tom Off Topic 8 04-06-2010 12:54 PM