Need help troubleshooting a possible EEC startup problem

I also did some reading in the book that was suggested in the thread. I looked at his MAP sensor and I don't see a hose connected to it. It doesn't have a normal tube with a ridge for a hose though. It has a white sleeve that surrounds the black tube with a squared off ridge. Is there supposed to be a hose to manifold pressure fitted to this module on the firewall.

It looks like this:
essure-sensor-bap-sensor-89-93-5-0-dy-530_fc8ce74b.jpg
 

LX1993

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I also did some reading in the book that was suggested in the thread. I looked at his MAP sensor and I don't see a hose connected to it. It doesn't have a normal tube with a ridge for a hose though. It has a white sleeve that surrounds the black tube with a squared off ridge. Is there supposed to be a hose to manifold pressure fitted to this module on the firewall.

It looks like this:
essure-sensor-bap-sensor-89-93-5-0-dy-530_fc8ce74b.jpg
That's a barometric pressure sensor. The speed density cars used a map sensor. Maf cars used those, supposed to be open.
 
MAF, Yes. No EGR or Canister. AIT and ACT yes. The computer is for an auto which is what's in the car. It's a..

EEC-IV SF1-MA12A A9P

O2 sensors is yes.


I realised that the ODB I reader only clears it's memory, not the computers codes. ( Since it just came back from rebuilding, would it still have the old codes stored? ) I'll clear them and get them read again.
 
I actually have a video! I'll post it shortly.. It doesn't like my server as a source for a media file, so you just get the audio from the MOV file.

Engine Start

Simply put, it is a little hard to start, then when it fires up, as long as you don't apply the throttle, it runs OK for about 10 seconds and shuts off. Restarting takes a few tries as it stumbles and dies. Once it stays running, it will continue idling until it warms up and then run OK. If you try to apply the throttle, it will stumble and die.

Ah, and it smells like it is running too rich.
 
Last edited:

General karthief

wonder how much it would cost to ship you a pair
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Can't see video,
Lets go back to some checks and balances, pull the plugs, are they black? If yes then change them, don't need nothing special just some good ol copper cheap autolites or motor craft, whatever is on sale. Well except Bosch.
This link is a checklist, print the list, just the list no need to print the rest of the thread, you'll need to reference this.
Find the two 10 pin connectors, there are often called the 'salt and pepper shakers' find the reference in the list for them, they show the pins for the injector wires, what you are doing is matching the connectors to correct injectors. The injectors are timed like the spark is timed.
A question about the timing pointer, is it on the passenger side of the balancer? Look through the list, there should be a pic of it, does it look like that?
Find top dead center on the #1 compression (TDC), pointer should be at 0* on the balancer. Is it?
Get these steps done, don't try to start the car.
One thing at a time.
There are some grounds we need to check too but will get to that, look through the checklist to see what we will be looking at.
 

Mustang5L5

Put lubricant all over the balls
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Here's a silly question that might have been answered already but I didn't read every post.

In an early thread you claim the wiring harness is 94-95 Mustang, but running an A9P.

Can you confirm the harness? Reason I ask is because the Sn95 5.0 engine harness is pinned differently than what a Fox ECU is expecting to see. Even within the 86-93 Fox years, the engine harness changed 4-5 times and the subtle differences would effect how it runs. It's really hard to mix and match harnesses with these cars. Also, the jumper on the O2 harness needs to match the ECU and the year harness you have. Since you have an A9P, the jumper needs to be set a specific way.
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
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polk county florida
Here's a silly question that might have been answered already but I didn't read every post.

In an early thread you claim the wiring harness is 94-95 Mustang, but running an A9P.

Can you confirm the harness? Reason I ask is because the Sn95 5.0 engine harness is pinned differently than what a Fox ECU is expecting to see. Even within the 86-93 Fox years, the engine harness changed 4-5 times and the subtle differences would effect how it runs. It's really hard to mix and match harnesses with these cars. Also, the jumper on the O2 harness needs to match the ECU and the year harness you have. Since you have an A9P, the jumper needs to be set a specific way.
I'm glad you jumped in here, I was looking for the differences in harnesses, the injector harnesses on top of the engine is basically the same right?
I'm getting him to start at the injector harness and work our way back to the ecu to verify what he has.
Won't stay running, pig rich.
 

Mustang5L5

Put lubricant all over the balls
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I'm glad you jumped in here, I was looking for the differences in harnesses, the injector harnesses on top of the engine is basically the same right?
I'm getting him to start at the injector harness and work our way back to the ecu to verify what he has.
Won't stay running, pig rich.


For a Mustang, the injector harness from 86-93 is the same. However it's different on the non-HO engine harnesses and truck harness.
 
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General,

Yep. I mentioned the forum softrware didn't like my file as web media. It's a simple MOV file. Click on the link to just listen.

"A question about the timing pointer, is it on the passenger side of the balancer?"

Yep. As I recall it is, Not the basic little wedge like my 65 Mustang. I'll be at the shop tomorrow, but I think it's like this:
Timing pointer

I already checked the timing much earlier in the thread. Here were the numbers. "it's about 32 degrees BTDC. With the plug removed, it's 12 degrees BTDC"

5L5,

"Can you confirm the harness?" It's a harness from " the donor " car. I wasn't involved in that step. How would I tell the difference. On that note, Dad has a new harness from Ford Racing that he intended to install, someday. I'm not sure, but I think the box mentions 1989. I'll know for sure tomorrow. Keep in mind this car ran well for years before Dad decided he was tired of the " Start, die, restart then runs fine " ritual. I don't think it did that to begin. So he spent money on a tank with a built in fuel pump and sender. No idea what pump is in it. To answer Tool's question. It does seem to have enough PSI when I tested it. 35-40psi. At least you guys gave me the OK when I posted those figures.
 
The salt and pepper shakers are white on white and black on black I don't know that you can swap them. I would like to see the connections cleaner inside. I didn't have any contact cleaner to do it. The sample spark plug I pulled out was sooty. It brushed right off. The timing indicator is the one I posted a picture of. I haven't checked for TDC, yet. Since it has run well in the past and we haven't moved the distributor at all, I don't suspect to find it off. I'll double check it.
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
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In the surging idle thread I linked in a previous post shows the pins in the white and black connectors, they are for the injectors, a picture shows what pins are for the injector connections, the cylinders are numbered, match the pins to each cylinder, you're making sure the connectors are on the right injector for that cylinder.
If it ran smooth before (only died) then the firing order is likely correct, injectors are timed the same as the firing order, it's possible the wrong injector harness was used.
Understand what I mean?
 
General,

I get it. Wouldn't it have run like heck all the time if the injectors were miss wired?

From 5L5...
"For a Mustang, the injector harness from 86-93 is the same."

Knowing my Dad the harness would have likely come from Mustang Village , our used to be local Mustang new parts and salvage yard. If so, I'm guessing it right.

I'm going to see about cleaning those connectors just because I like to see nice shiny metal on important stuff.
 
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Sorry for the long delays between posts. I put a new battery in the ODB1 tester and put new spark plugs in the car. It sort of changed the symptoms. Some better and some worse. I'll start with the codes.

KOEO:
56, 81,82,84,85, then 10 and 11

KOER:
12, 33, 44, 94

Starting the car was a little different. Ist try, started and died right away. Second try was the same but it tried to run just for a moment. The third try it ran but the idle was so slow it almost died before I could give it a bit of throttle to bump it up. It was not idling smoothly. I quickly through a timing light on it and the idle was in the 550-620rpm range. The timing was moving around from the low 20s to low 30s btc. I couldn't tell for sure since it was not very stable. Last week, at this point, I pulled the SPOUT plug and it ran better without it. I left in in this time. I let it run until it looked to stop getting warmer which was about 160 on the gauge, but a laser temp gun said the thermostat housing was no more than 130. It still would drop the rpm enough that I would give it a goose, which it did fine, to keep the car from trying to die. Once it was warm I ran the KOEO scan. When I tried to restart it, for the next scan, it would start and instantly die about 3 or four times and then ran with a very low throttle until I could give the car a rev. Each time it died, I made sure the fuel pump primed each time and stopped before I tried to start it.

The 56 code is new. MAF sensor too high. I don't believe he has any trans oil sensor to give the alternate code.
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
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Go over all the vacuum lines, replace as necessary, paying attention to the canister purge line, it sourced for under the front of the upper intake and not easy to see.
Clean the maf sensor, use electrical cleaner, some cleaners like carb cleaner may damage it.
I would yank the upper intake off, that gives you access to all the connections and the pcv and hose. Replace/repair one at a time.
I am not a mechanic in real life but I've managed to fool alot of people around here so repair at your own risk, burn outs and doughnuts optional.