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can you keep it running with carb or comb chamber cleaner?

you have a stock untouched throttle body?
 

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Discussion Starter #22
Will try that this afternoon.
It’s an accufab 75mm throttle body with stock rubber elbow, MAF sensor and air box. Planned on upgrading MAF sensor and injectors but until this gets figured out I was gonna leave stock injectors and MAF sensor/housing.

Quick backstory on why computer was replaced.

Drove car to a shop 2 hrs away last October to have cowl panel replaced, got crushed from hood flipping up and never could get the wipers to wipe good. Drove car on 6 hour trip just a few months prior, no issues. Last 15 min of commute to shop the car started sputtering, low rpm, like it wanted to kill. Made it to the shop but thought nothing of it since it had run flawless before. Shop noticed the cowl bucket was rusted out in the corner over the computer. Fixed that and replaced cowl. Shop started the car and ran like it did when I dropped it off, then the EEC relay melted. Shop changed it but car wouldn’t start or turn over. Took the computer out and had a rust hole in the case and saw internal issues,’probably due to water that came from rusted cowl bucket. Replaced the computer and here we are. Car will start but instantly dies with all sensors plugged in. Car sounds like it has a huge cam in it with a lot of lope and idles at 550 rpm with sensors unplugged. Car used to have a nice very flat idle which is what i wanted and rationale for sticking with the stock cam.
 

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Discussion Starter #24
Made a jumper and put some spades on the end, electrical cleaner the test ports.

Got codes:

54
31
67
81
85
84

Shop also installed all new AC components including a sanden compressor. Does this look right?

1061806
1061807
 

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looks good to go!!

should you address the codes?

did you code read with the ACT disconnected
 

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does it respond to throttle at all during this time before it stalls? I just dealt with a burnt pin 46 tracer on a computer last week and it di exactly as you're describing prior to having the computer repaired.
 

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Highly unlikely to have that, as you would expect all the sensors that share that ground to produce a DTC, that is not what the poster has happening
 

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Discussion Starter #28
Well shoot I forgot to plug the ACT sensor in when checking the codes... I guess that explains the code 54...

What is a DTC?

I got the itch to check my grounds again and didn’t like the black electrical tape glue marks on the inner fender so decided to disconnect the connectors under the MAF meter.

I’m ashamed to say that it appears my bad quality harness lengthening job I did about 8 years ago (to hide wires, then changed my mind and put everything back in the bay) might be the cause of this.

Found this wire that came apart on the main HEGO harness.

Gonna go get a heat shrink gun, heat shrink tubing and attempt a quality repair job and report back.

Would this cause the start no run condition I had? Wonder why I didn’t see a code for this...

1061842
 

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Discussion Starter #29
Damn I’m an idiot that’s the mass air flow sensor, thought it was the HEGO plug. Gonna repair it and see what happens.
 

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Discussion Starter #31
Haha!!!

Well i’ll be damned that was it. Cut out the lengthened part and just joined the old wires together and voila, sucker started right up and idled perfectly and doesn’t kill anymore.

Damn it’s hard to do a good job on soldering and heat shrink. Use a heat shrink to big and it don’t seal right and use the one that looks to fit the best and can’t get it past the joint. I just put some electrical tape on this small part and zip tied them together to keep them from moving too much.

I appreciate your attention to this matter Indy2000!

1061845
 

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Just FYI

if you had a tuning device that logs, this could have been seen this in the first 20mins

the factory tune, is designed to run, without a maf

its limp mode

little known fact, when you change engine breathing, the factory limp mode will not work, as you have found out

another reason tuning is needed
 

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Discussion Starter #33
What do u mean engine breathing, like the trick flow heads and explorer intake, etc?

Where would a tuning device connect on this car?

I did not realize that, thanks for sharing the knowledge sir.

I’ve had the car a while and it was kind of my learning car. Unfortunately every once in a while my quality of work on something I did years ago or something I had someone do a long long time ago rears it’s ugly head up.
 

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whatever you changed, that will make the engine breathe differently than is in the stock tune

that is what i mean
 

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In other words the heads, intake, throttle body have all been upgraded. It would be beneficial to have the car tuned.

Sent from my moto z3 using Tapatalk
 

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In your first post you mention a MAF voltage of 0.4 volts

so which wire was open on your maf?
 

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In other words the heads, intake, throttle body have all been upgraded. It would be beneficial to have the car tuned.

Sent from my moto z3 using Tapatalk
It would be, if you desire near stock like driveability
 

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Discussion Starter #38
In your first post you mention a MAF voltage of 0.4 volts

so which wire was open on your maf?
Yep, I had checked pins c and d and got that voltage. The red wire was open which was pin a.

I had barely used a multimeter prior to this and thought nothing of it when I couldn’t get a readout between pins a and b.

Feel better about knowing how to check voltage, continuity, amps, and ohms now, was a good experience.

Question, I need to have my hood repaired (small bit of weld) by the hood latch boss where the opening is that pushes down the latch lever when u close the hood because the metal that grabs the latch is ripping. If someone where to weld those cracks for me would that mess up any circuits, sensors, or computer? The hood of is almost insulated from the car except the prop rod.
 

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Disconnect the battery

Sent from my moto z3 using Tapatalk
 
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