Please Help With 77 Dodge Aspen With A9l, T5, 5.0l Swap. Starts Then Dies

Jalopychaser

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Apr 25, 2017
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24 hours of lemons racecar. Budget build because I have a very strict spending limit on your car. Anyways....

I got a 1990 (I think) mustang 302, sn95 t5, 1991 a9L (I rhink) and 1991 (I think) harness. Apparently all of the parts came from stick shift cars. And I have a couple different oxygen sensor harnesses (not using) And I have a 77 dodge aspen shell.

Anyway I put it all into the Aspen, did not use a transmission harness, no vss, no Evap no ac cut out, no fuel pump relay, no emissions, nothing that wasn't necessary. did not use an oxygen sensor harness. Sent "key on" 12v to both oxygen sensors and pinned the return signals and grounds directly to the computer like tmoss pinout diagram shows. Did not use any of the eec relays or anything on the harness no switches or sensors on clutch or tranny

Literally all I'm using is a barometric sensor, engine coolant temperature sensor (on the heater core pipe/rail), intake air temperature sensor (on the gt40 manifold), mass air sensor, both oxygen sensors, tps, idle speed bypass control thing, distributer with tfi mounted on it, and coil. I have everything wired up and triple checked and functioning somewhat properly. I followed Tmoss pin out diagram on only the necessary stuff. I sent "key on" 12v to pins 37, 57, The ignition coil positive side, the "run" lead on the distributor, maf, idle speed control, and all 8 injectors. "Start only" 12v to corresponding pin on distributer harness, made sure I used a 20 2K resistor right before the ECU on the corresponding wire I grounded all of the grounds. And pin 1 has a constant 12v volts for the Memory. I checked the tps voltage .92 or .94 I don't remember exactly which one. I just remembered checked out good

It fires right up and sounds great smooth and strong for 3 to 5 seconds until it shuts off. I can kind of keep it running by using the throttle. If I keep opening and closing the throttle real carefully it will rev up and die down and sputter and then rev up. Can barely keep it running using the throttle. I can occasionally get it to rev up to about 2 grand by feathering the throttle and it sounds great at 2 grand but it will not idle and to get to 2 grand I have to carefully feather the throttle open and closed a couple times and getting to 2 grand it is really choppy and sputters a lot. And then at like exactly 2 grand it sounds fantastic and then drops back down and dies. It won't idle on its own. It seems like when it first fires up the RPMs are good and high and then in a few seconds when the RPMs would want to drop down to Idle is when it doesn't do that and just shuts off

I did not do anything with pin 30. I have no jumper installed anywhere on the oxygen sensor harness because I'm not using one. I did not jump or bypass any other wires on the harness I simply left everything I'm not using unhooked and only hooked up what I am using. So I'm not sure if I need to do something with that pin 30 or if the computer thinks that the clutch is not Pressed in or that it is in gear or something I have no clue. The fuel system is a fuel-cell with adjustable fpr, in line pump wired to relay, and "key on". I've been trying to check and see if I'm losing injector pulse or the ignition signal when it dies, but it's hard to figure that out because when it dies you lose those signals anyway. Whether the computer is shutting off the injector pulse for some reason three seconds after start up. Or if the pip is doing something silly 3 seconds after start up.

For some reason and after reading a whole bunch of different posts about 1030 and 46. Jumpers on O2 sensor harnesses and all that other stuff I am leaning to believe that I need to jump something or cut something or bypass something. But then again at the same time i'm not sure that I need to do that because I don't have a vehicle speed sensor, no clutch switches, no NDS, none of that stuff. Literally have a battery switch a starter button and a couple engine sensors tied into the computer.

I've got to be missing something any help would be fantastic the races in two weeks the car still has to go get tuned and get an alignment


If anyone wants to call me and help me walk through something my number is 610-312-4269 I know sometimes people like to talk over the phone and explain things better than typing but any kind of responses that all would be fantastic
 
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Am I supposed to ground pin 46 or 30 or somehow trick the EEC into thinking that a trans harness is installed with all the correct switches and all? I don't have a damn clue I am lost. I just need this thing to run so I can send it to get tuned and alignment asap. maybe I have the burned-out trace on the computer or something? Any responses for any tests to do or any wires to jump to anything would be great. Another note, it appears that pin number 30 from the EEC has a positive output of 5 V. Some people on other formus have said before to just attach pin 30 to pin 46. To me that would just create a dead short and fry something. But hell, what do I know I'm here asking questions trying to get my car to run LOL
 
I wouldn't focus too much on pin 30 as without the jumper correct, the car will still run and drive.

I'm almost curious if you could dump codes, what the ECU would say it isn't liking. Do you still have the self test connector in the harness?

It will give a clue as to if something is majorly wrong...like if you see codes for the MAF sensor even if it's hooked up.

Is going carb an option?
 
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I also did not use the factory low oil sensor or the oil pressure sensor. So right now there is no oil info getting back to the ecu. Ecu could be shutting it down since it doesn't have any oil input?
 
Nope non of that stuff matters.

This is simple efi you have everything it needs to run. Can you get a fuel pressure reading off the Schrader valve for us?

Pulling codes can be done with a paper clip or 12v test light.

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Also great resource.
Www.veryuseful.com
 
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I have a gauge right on The fuel rail. It is about 42 psi ish right around there. That is as low as I can get the adjustable fuel pressure regulator to go.

When I have a node light on the injectors it's nice and bright as soon as the engine fires and then it slowly trickles down and gets dimmer as the engine dies. I checked the 12v to Injectors. It doesn't does down as engine does. Not sure if I need to ground pin 46 or maybe have a weak ground at ecu or sensor (but I double checked all the ecu grounds) or a weak pip that dies down and sends weak signal to ecu. I don't have an oscilloscope to test the pip signal. I have very good fluke digital meters and node light set
 
Do not connect pin 30 and pin 46. Doing so will instantly fry the EEC.

During start, on automatic cars, pin 30 will see voltage, while on manual trans cars it will not. Since you missing/spliced harnesses, it's tough to predict what will happen here, but ultimately, with the ECU out, if you crank the engine, you should see ZERO volts on pin 46.
 
I wasn't able to pull codes yet. I am disconnecting the computer and letting it sit for a little bit to reset and then I'm going to crank on it a couple times and then see what fresh codes I have. Nothing on this computer is tied into the starter solenoid so the starter solenoid is not sending voltage to anything like it would be in a stock wired car. With just the ignition circuit and ecu powered. It's sending voltage out of pin 30. I didn't wire it to anything I just left it alone
 
Let's skip pin 30 for now, and focus on pin 46. It's a filtered ground for the various sensors shown in the above diagram. 5V on this wire could cause havoc with the ecu and burn out a trace (easily repaired)

So, with the ECU disconnected, if you test pin 46 to ground, do you have voltage when cranking the engine over?
 
Remove the ECU and test the harness side of pin 46 under the following conditions

Ignition on
ignition off
ignition on clutch in (skip this if you have no clutch switch sensor to the ecu)
ignition on cranking with clutch in
ignition on cranking with clutch out.

You should have 0 volts on pin 46 in all conditions
 
Cranks OK, but No Start Checklist for Fuel Injected 5.0 Mustangs model years 1986-1995

A word about this checklist before you start: it is arranged in a specific order to put the most likely failure items first. That will save you time, energy and money. Start at the top of the list and work your way down. Jumping around will possibly cause you to miss just what you need to see to find and fix the problem. Don’t skip any steps because the next step depends on the last step working correctly.


Revised 15-Sep-2014 to add temporarily bypassing the MSD box if it is present.

All text applies to all models unless stated otherwise.

Note: 94-95 specific changes are in red

1.) Remove push on connector (small red/blue wire) from starter solenoid and turn ignition switch to the Run position. Place car in neutral or Park and set the parking brake. Remove the coil wire from distributor & and hold it 3/8” away from the engine block. Jumper the screw to the big bolt on the starter solenoid that has the battery wire connected to it. You should get a nice fat blue spark.
Most of the items are electrical in nature, so a test light, or even better, a voltmeter, is helpful to be sure they have power to them.

No spark, possible failed items in order of their probability:
A.) MSD, Crane, or other ignition box if present - Bypass it and return to stock configuration if possible. Do this as a temporary measure to eliminate it as a possible problem source.
B.) PIP sensor in distributor. The PIP sensor supplies the timing pulse to trigger the TFI and injectors. A failing PIP sensor will sometimes let the engine start if the SPOUT is removed. See paragraph 5A – Using a noid light will tell if the PIP is working by flashing when the engine is cranking.
C.) TFI module: use a test light to check the TFI module. Place one lead of the test light on the red/green wire on the ignition coil connector and the other lead on the dark green/yellow wire on the ignition coil connector. If the TFI is working properly, the test light will flash when the engine is cranked using the ignition switch.
D.) Coil
E.) No EEC or computer power - EEC or computer relay failure
86-93 models only: EEC relay next to computer - look for 12 volts at the fuel injector red wires.
94-95 models only: EEC or PCM power relay in the constant control relay module. Look for 12 volts at the fuel injector red wires.
Both 86-93 and 94-95 models: No 12 volts with the ignition switch in the run position on the fuel injector red wires. The relay has failed or there is no power coming from the ignition switch. Make sure that there is 12 volts on the red/green wire on the coil before replacing the relay.
F.) No EEC or computer power - fuse or fuse link failure
86-93 models only: Fuse links in wiring harness - look for 12 volts at the fuel injector red wires. All the fuse links live in a bundle up near the starter solenoid. Look for a 20 gauge blue fuse link connected to 2 black/orange 14 gauge wires.
94-95 models only: 20 amp EEC fuse in the engine compartment fuse box. Look for 12 volts at the fuel injector red wires.
G.) Ignition switch - look for 12 volts at the ignition coil red/lt green wire. No 12 volts, blown fuse link or faulty ignition switch. Remove the plastic from around the ignition switch and look for 12 volts on the red/green wire on the ignition switch with it in the Run position. No 12 volts and the ignition switch is faulty. If 12 volts is present in the Run position at the ignition switch but not at the coil, then the fuse or fuse link is blown.
Note: fuses or fuse links blow for a reason. Don’t replace either a fuse or fuse link with one with a larger rating than stock. Doing so invites an electrical fire.
Ignition fuse links may be replaced with an inline fuse holder and 5 amp fuse for troubleshooting purposes.
94-95 models only: Check inside fuse panel for fuse #18 blown – 20 amp [fuse
H.) Missing or loose computer power ground. The computer has its own dedicated power ground that comes off the ground pigtail on the battery ground wire. Due to it's proximity to the battery, it may become corroded by acid fumes from the battery.
In 86-90 model cars, it is a black cylinder about 2 1/2" long by 1" diameter with a black/lt green wire.
In 91-95 model cars it is a black cylinder about 2 1/2" long by 1" diameter with a black/white wire.
You'll find it up next to the starter solenoid where the wire goes into the wiring harness
I.) Computer. Don’t replace the computer just because you don’t understand how it works. Computers seldom fail, it usually is a sensor or wiring problem that causes the problems.
J.) Bad or missing secondary power ground. It is located between the back of the intake manifold and the driver's side firewall. It supplies ground for the alternator, A/C compressor clutch and other electrical accessories such as the gauges.
K.) Engine fires briefly, but dies immediately when the key is released to the Run position. Crank the engine & when it fires off, pull the small push on connector (red/blue wire) off the starter relay (Looks like it is stuck on a screw). Hold the switch in the crank position: if it continues to run there is a problem with either the ignition switch or TFI module. Check for 12 volts at the red/green wire on the coil with the switch in the Run position. Good 12 volts, then replace the TFI. No 12 volts, replace the ignition switch.

Wiring Diagrams:

See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host) for help on 88-95 wiring Mustang FAQ - Engine Information Everyone should bookmark this site.

Ignition switch wiring
http://www.veryuseful.com/mustang/tech/engine/images/IgnitionSwitchWiring.gif

Fuel, alternator, A/C and ignition wiring
http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

Complete computer, actuator & sensor wiring diagram for 88-91 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

Complete computer, actuator & sensor wiring diagram for 91-93 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/91-93_5.0_EEC_Wiring_Diagram.gif

Complete computer, actuator & sensor wiring diagram for 94-95 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/94-95_5.0_EEC_Wiring_Diagram.gif


AutoZone wiring diagrams: You can navigate to the diagrams yourself via Repair Info | AutoZone.com and select the car year, make, model and engine. That will enable you to bring up the wiring diagram for your particular car.

2.) Spark at coil wire, pull #1 plug wire off at the spark plug and check to see spark. No spark, possible failed items in order of their probability: [/b]
A.) Moisture inside distributor – remove cap, dry off & spray with WD40
B.) Distributor cap
C.) Rotor
D.) Spark Plug wires
E.) Coil weak or intermittent - you should see 3/8" fat blue spark with a good coil

3.) Spark at spark plug, but no start.
Next, get a can of starting fluid (ether) from your local auto parts store: costs a $1.30 or so. Then pull the air duct off at the throttle body elbow, open the throttle, and spray the ether in it. Reconnect the air duct and try to start the car. Do not try to start the car without reconnecting the air duct.

Two reasons:
1.) If it backfires, the chance for a serious fire is increased.
2.) On Mass Air cars, the computer needs to measure the MAF flow once the engine starts.
If it starts then, you have a fuel management issue. Continue the checklist with emphasis of fuel related items that follow. If it doesn’t, then it is a computer or timing issue: see Step 4.

Clue – listen for the fuel pump to prime when you first turn the ignition switch on. It should run for 2-4 seconds and shut off. To trick the fuel pump into running, find the EEC test connector and jump the connector in the Upper RH corner to ground. The EEC connector is near the wiper motor and LH hood hinge.

attachment.php?attachmentid=68357&stc=1&d=1322348015.gif


If the relay & inertia switch are OK, you will have power to the pump. Check fuel pressure – remove the cap from the Schrader valve behind the alternator and depress the core. Fuel should squirt out, catch it in a rag. Beware of fire hazard when you do this. In a pinch, you can use a tire pressure gauge to measure the fuel pressure. It may not be completely accurate, but you will have some clue as to how much pressure you have. If you have any doubts about having sufficient fuel flow/pressure, rent a fuel pressure test gauge from the auto parts store. That will tell you for sure if you have adequate fuel pressure.


4.) No fuel pressure, possible failed items in order of their probability:
A.) Tripped inertia switch – Coupe & hatch cars hide it under the plastic trim covering the driver's side taillight. Use the voltmeter or test light to make sure you have power to both sides of the switch
B.) Fuel pump power relay – located under the driver’s seat in most stangs built before 92. On 92 and later model cars it is located below the Mass Air Flow meter. Look for 12 volts at the Pink/Black wire on the fuel pump relay.
C.) Clogged fuel filter
D.) Failed fuel pump
E.) 86-90 models only: Blown fuse link in wiring harness. Look for 12 volts at the Orange/Lt Blue wire on the fuel pump relay.
91-93 models only Blown fuse link in wiring harness. Look for 12 volts at the Pink/Black wire on the fuel pump relay.
The fuse links for all model years 86-93 live in the wiring harness near the starter solenoid.
94-95 models only: 20 amp fuel pump fuse in the engine compartment fuse box. Look for 12 volts at the Dark green/yellow wire on the constant control relay module.
F.) Engine seem to load up on fuel and may have black smoke at the tailpipe. Fuel pressure regulator failed. Remove the vacuum line from the regulator and inspect for fuel escaping while the pump is running. If fuel is coming out the vacuum port, the regulator has failed. Check the regulator vacuum line for fuel too. Disconnect it from the engine and blow air though it. If you find gas, the regulator has failed.

5.) Fuel pressure OK, the injectors are not firing.
A.) The PIP sensor in the distributor tells the computer when to fire the injectors. A failing PIP sensor will sometimes let the engine start if the SPOUT is removed.
A noid light available from any auto parts store, is one way to test the injector circuit to see if the injectors are firing. The noid light plugs into the fuel injector harness in place of any easily accessible injector. Plug it in and try to start the engine: it will flash if the injector is firing.

I like to use an old injector with compressed air applied to the injector where the fuel rail would normally connect. I hook the whole thing up, apply compressed air to the injector and stick it in a paper cup of soapy water. When the engine cranks with the ignition switch on, if the injector fires, it makes bubbles. Cheap if you have the stuff laying around, and works good too.
B.) Pull an injector wire connector off and look for 12 volts on the red wire when the ignition switch is on.
C.) No power, then look for problems with the 10 pin connecter (salt & pepper shakers at the rear of the upper manifold).

See the graphic for the 10 pin connector circuit layout.
?temp_hash=3ef2497fff29a7a9daee955cf93e5805.jpg

The injector power pin is the VPWR pin in the black 10 pin connector.


D.) No power and the 10 pin connections are good: look for broken wiring between the orange/black wire on the EEC relay and the red wire for the 10 pin connectors.
E.) TPS voltage exceeds 3.7 volts with the throttle closed. This will shut off the injectors, since the computer uses this strategy to clear a flooded engine. Use a DVM, a pair of safety pins, and probe the black/white and green wires to measure the TPS voltage.
On a 94-95 Mustang, probe the black/white and grey/white wires to measure the TPS voltage.
It should be .5-.1.0 volts with the key on, engine not running. Note that if the black/white wire (signal ground) has a bad connection, you will get some strange readings. Make a second measurement using the battery post as the ground to eliminate any ground problems. If the readings are different by more than 5%, you may have a high resistance condition in the black/white signal ground circuit.

6.) Spark & fuel pressure OK.
A.) Failed IAB or improperly set base idle (no airflow to start engine). Press the throttle ¼ way down and try to start the car. See the "Surging Idle Checklist for help with all your idle/stall problems.
B.) Failed computer (not very likely)
C.) Engine ignition or cam timing off: only likely if the engine has been worked on recently. If you removed the distributor, there is a good probability that you installed it 180 degrees out of time.
D.) Firing order off: HO & 351 use a different firing order from the non HO engines.
HO & 351W 1-3-7-2-6-5-4-8
Non HO 1-5-4-2-6-3-7-8
E.) No start when hot - Press the throttle to the floor & try starting it, if you get this far. If it starts, replace the ECT.
F. ) Engine that has had the heads off or valves adjusted. Do a compression test to make sure the valves are not adjusted too tight. You should have a minimum of 90 PSI on a cold engine.
 
Here's what I got today after 12 hours of messing with this thing and triple checking every ding letter wire.

I got it to stay running and idle on its own but there's a catch.... with 100+psi of fuel pressure

Thinking injectors may be clogged (they were sitting around in a box of parts for a while. And cutting through the stainless branded lines and the rubber inside while making the lines probably netted some debris in the lines.

Or

The output signal from ecu to the injectors is so weak for some reason that running a such high fuel pressure is compensating for that. I have a great damn near/no resistance connection to 12v at all of them. And salt and pepper shakers in mint condition. And I checked resistance of all injector wires earlier and they all checked out great from eec harness to each pin at injectors. Maybe computer output is weak to the injector. While testing them with node light sometimes it's brights as :poo: sometimes it dims down. But I can't tell if that's the computer just maintaining the idle or of some reason something is wrong and it gets weak. Brand new tfi, pip, dizzy,

Gonna check that pin 46 condition later tonight