81 spyder stops/stalls LETS START FROM SCRATCH

[ptmassa]

Disregard allllllllllllllllllllllllll previous. I started from scratch. I put everything back to the way it was before I did step one of troubleshooting. I will run through what I found. Can we start from scratch, i have gone in too many directions and need to just double check everything I have done.

Car cranks, coughs and sputters but never starts. Fuel pressure is 42 psi at fuel injectors. All spark plugs, wires, cap rotor replaced new. Spark is good at each plug. No fuel injector spray into any cylinder. I believe it was ZACHMAC who had sent me trouble shootig from wcmotors.com. I started fresh with the 13 page diagnostic guide supplied.
No voltage at fuel injector connector. Per the guide I went to the dual relay next. Connected test light between 88Z and 85 terminals. No light on. I connected 88Z wire to ground and test light came on. Per the guide the next step is to replace the ECU.
Now I am by no means a genius, but 85 wire is a ground. I jumped ground to 85 wire, went back out to the injectors and low and behold there is voltage there now. I returned to the dual relay and completed the terminal checks on 86c,88a,88e,88b using terminal 85 with the modified ground. I then went to the ECU harness. Checked terminal 1 to ground. then checked terminal 1 to 5,16, and 17. Per the guide if the light lights to this point replace the ECU. Same info as I got when I found 85 wire no good.
Being as I know I am not a genius, I realize that the temporary repair of wire 85 is by no means the go ahead and finish the trouble shooting. Pretty cut and dry no circuit between 88z and 85; replace the ECU.

Am I looking for a problem that I will not find without an ECU replacement? Any suggestions other than going back and checking air flow meter, coolant sensors, thermo time switches? I had no voltage at injector harness, I checked 88z to 85, failed the test, is ECU replacement my next step?

[rlux4]

I believe KD (owner of Wine Country Motors) made that diagnostic manual section available after helping me out when I first got my car and had intermittent stall/no start problems. What I found out while going through the steps was the same thing you're finding, at certain points it says to replace the ECU. What it should say is it may be necessary to replace the ECU. I also reached the point where it looked like I had a bad ECU, but it was not the problem, it was power to the ECU causing the problem. This may not be your problem but before you go to the expense of buying a replacement ECU I'd reccommend that you first check all three power sources going into the dual relay. 1: Pink wire hot with the ignition switch "on" 2: Brown wire with white stripe hot with the key in "start". 3: The heavy brown wire coming directly from the battery. If all three sources are good, then it may be the ECU. Do you know anyone in your area with a FI car? An easy way to tell is to borrow a known good one and plug it in your car, see if it solves the problem.
Ron

Edited to correct info. I goofed on #2, the green with black stripe coming out of the dual relay going to the fuel pump has power when the flap is open.

[ptmassa]

I believe KD (owner of Wine Country Motors) made that diagnostic manual section available after helping me out when I first got my car and had intermittent stall/no start problems. What I found out while going through the steps was the same thing you're finding, at certain points it says to replace the ECU. What it should say is it may be necessary to replace the ECU. I also reached the point where it looked like I had a bad ECU, but it was not the problem, it was power to the ECU causing the problem. This may not be your problem but before you go to the expense of buying a replacement ECU I'd reccommend that you first check all three power sources going into the dual relay. 1: Pink wire hot with the ignition switch "on" 2: Brown wire with white stripe hot with the flap in the AFM open, either by hand or when cranking. 3: The heavy brown wire coming directly from the battery. If all three sources are good, then it may be the ECU. Do you know anyone in your area with a FI car? An easy way to tell is to borrow a known good one and plug it in your car, see if it solves the problem.
Ron

The pink, brown with a white stripe, and large brown wires are all hot. I verified this by doing the checks I has listed. The pink, or the brown with white stripe, at one point were an issue to someone( I am not original owner). Someone at some point installed a scotch lock connector between these 2 wires. they must have had one of these with no power and rather than find and fix the cause they stole power from one for another. As far as borrow an ECU, no one in this area that I know that could supply a loaner for testing reasons.

[narfire]

I have a spare if you want to check, but it would take a week to get there and I'd like it back as a spare if mine packs it in. Let me know and I'll mail it off tomorow if you want. (pm with address)
Chris

[ptmassa]

I have a spare if you want to check, but it would take a week to get there and I'd like it back as a spare if mine packs it in. Let me know and I'll mail it off tomorow if you want. (pm with address)
Chris

most excellent of you. I sent a PM your way. thanks for the help.

[rlux4]

Chris, that's very thoughtful of you. I also have a spare which I had planned to offer if there was no one in the area to borrow one from. If shipping is more reasonable from California than it is from BC, mine is also available to use as a tester.
Ron

[zachmac]

While it is possible it's the ECU, it is also highly unlikely. When I was troubleshooting my car Mark Allison mentioned that he has only seen two go bad in 30+ years of Fiat wrenching and both of those were clearly fried by electrical shorts.

The pink wire mated to the brown/white is definitely NOT GOOD. The brown/ white is the main HEAVY GAGE feed to the fuel pump through the relay. The pink wire is a feed from fuse 1 that is supposed to power the coil to close the FI contacts when you first turn on the key.

Now either the brown/white is feeding the pink or the other way around. Do you know which it is? BTW, you know that the brown/white is fused in a holder right above the fuse box in the tangle of wires. If you remove the two screws holding the fuse box in it is easier to get to it. It may be some PO simply didn't know about it and didn't realize he had a blown fuse (which kills the white / brown feed wire).

If the pink wire feeds everything then most likely you are trying to feed the fuel pump through and inadequate gauge wire. If the white /brown is feeding the pink then you would be picking up the first relay contact set constantly (un-switched power). I suspect you have the latter case, pink wire feeding everything. I HIGHLY recommend you fix these wires before everything else. It may even go a long way toward fixing the overall problem. Low voltage to the relay for the pump can cause a lot of weird stuff.

[ptmassa]

I definately know that overall I will need to repair tha mated wiring hodge podge. I would agree with the low voltage to the fuel pump, but there is 42 psi pressure at the fuel rail. If the pump is experiencing low voltage it must be intermittent, and not when I checked the pressure. I in no wway am saying that the ECU is the culprit. The troublshooting sheets I am using are telling me it is. I have alot 20 years experience with heavy trucks, and I have seen ver very few ECM failures. Usually something that looks like an ECu/ECM failure winds up being an electrical issue. Unfortunatley, everytning I am using to help me find the issue is telling me that if terminal 85 at the dual relay fails th check then the ecu has failed. A member ha offered to let me use a spare of his for a quick check. I have my fingers crossed that I plug it in and vroooom vroooom, but I am not holding my breath. If the car does not start with the ECU I know I have a different issue. If it dies then I am onto a quick spin around town. I have never heard this car run, in the past 5 years it has been started 2x. I have many many issues needing attention, for now I just want to get it to start when I turn the key. Will keep the post updated as I learn more. Thanks for everyones ideas and advice, much appreciated.

[zachmac]

You say the car won't start so clearly you are testing fuel pressure while cranking. In your earlier posts you had stated that the second set of contacts in the combination relay close when cranking but reopen when you release the key to run. The fuel pressure regulator is vacuum actuated. If you don't start then it doesn't relieve fuel back to the tank and even a short FP run can build pressure. Did you ever try the suggestion of cranking, hold the contacts closed manually and release the key to see what happens? If the second set of contacts is opening then it is an electrical NOT ECU problem.

BTW, does the car fire while cranking? You mention sputter? if you keep cranking does it run until you stop?

[ptmassa]

One half of the relay, white bundle of wires, closes when you turn the key to the on/run position. Second set of contacts( 5 wire bundle pink, brown large, brown with white stripe etc....) close when the key is turned to the crank position. As long as the key is on the contacts, white bundle wiring, are closed. I have manually closed the contact on the second bundle, pink and 2 browns. with the key on, this contact closed , the fue pump runs.
The car, when cranking, does not fire everytime. If I crank and stop 10x it will fire and "cough/sputter" for 10-15 seconds when I release they key to the run position. This DOES NOT happen everytime I attempt to start it.
I am hoping that the ECU is not the issue as i do not look forward to buying one. VERY COSTLY repair. I have restarted my diagnostic checks 6x since yesterdays post. Using the info I have fuel and spark are the first checks. They check good. 3rd step is voltage at injectors. There is voltage there( both sides of the 2 pin connector) but no ground. At this point in the diagnostics I am directed into the car to the dual relay. IF I HAD POWER AND GROUND AT THE INJECTOR HARNESS I WOULD GO ON TO COOLANT TEMP SENSOR, THERMO TIME SWITCH, AIR FLOW METER AND THEN EVENTUALLY INTO THE DUAL RELAY. In the guide I am using I am told to skip those checks as I have no ground at the injector harness. I have no ground on the 85 wire at the dual relay. This goes to the 29 post on the ecu, which supplies ground to either side of the relay. Using the info i have to do my checks I am told ECU replcement.
I can manually establish a ground at the 85 wire, then I do have a good check light at the injector harness. i have gone through the trouble shooting from start to finish with the manual ground on the 85 wire in place. All items check out right to the final step number 18. Last check I have to do is ECU pin from 1 to 17. Test light shows power at 1 and ground at 17. At this point the guide tells me to replace the ECU. Like I said I am hoping an ECU is not the issue, but at this point until I eliminate that from the puzzle I feel I am running in circles.
Here is the million dollr question. DOES ANYONE KNOW IF MANUALLY SUPPLYING THE GROUND TO THE 85 WIRE WILL WORK THE SAME AS IF IT WAS ESTABLISHED THRU THE 29 PIN AT THE ECU????????????????????????????. If so then the fact that the 29 pin at the ECU is not a good ground would not matter. If you cannot manually bypass that pin then me manually doing it is doing nothing for me other than confusing me to no end.

[rlux4]

Do you have Brad Artigue's wiring diagrams? if not, you need them, get em' here:
http://artigue.com/?page_id=3
You're right, #85 on the dual relay is ground, and should be constant, regardless if the key is in or not. So to see if the ground making it from the ECU to it, check on the ECU pigtail at terminals 5, 16 and 17 to see if you have continuity to ground.Then check the dual relay wire at contact 88z for continuity to ground.
I'm also pretty sure it's not the ECU, but a lot of people have been where you are and because a lot of diagnostics point to it end up putting in another only to find out it was something else.
As to your question about taking a direct ground to 85, I wouldn't know, there's so much in this system that we're not privy to. I don't know of anywhere available that would show an ECU internal schematic for instance.
Ron

[SpiderJim]

I had a similar problem. Spent a couple of days trying to figure it out. Crank start splutter stop! Turns out my full gas tank had been siphoned off by bad people or persons. Just a thought? Good luck

[ptmassa]

Thanks for the suggestion. Car sat for many years. I have drained and refilled with new gas. Took another look at the gas after reading this. Good thought, but no luck. Thanks though.
Waiting on loaner ECU, crossing fingers it is not that. will update the post when it comes.

[narfire]

The package is in the US, on its way...
Chris

[ptmassa]

Ok, update to this frustrating car. Got the loaner ECU. I have no garage at my house so my work is always in conjunction with the weather. Opened the package, removed ECU, intalled into car. With my ECU in place #28 wire at the dual relay wa NOT a good ground. I could run a jumper to the 28 wire at the dual relay and get good readings from everywhere I looked. Plugged the loaner
ECU in. #28 wire had good ground. Dual relay worked properly, power and ground to fuel pump. Good power and ground to fuel injectors. Car cranked but still did not start. Rechecked fuel pressure. Ranges between 39-42 psi while cranking. God was against me and the rain started coming. Called it quits for that day. REMOVED loaner ECU.
Flas forward to today, rain is gone ground is dry again. Plug loaner ECU in.........................NO GOOD GROUND at the 28 wire at the dual relay. Everything works as if it did before installing the loaner ECU. Once again I can jump a good ground to the 28 wire. Scratching head. Syarted from scratch yet again
1) Coolant temp sensor test at ECU plug. Terminal 13 to ground I have 3800 ohms. Passes test
2)Check Thermo time switch. Get no continuity at switch while cranking engine. 77 degrees today so I should not get any. Passs test.
3) Check cold start valve. operates correctly.
4) d air flow sensor. Removed cover door oprates freely. Cleaned sensor connections. Check resistace at ECU plug.
A) check between pins 6 and 8. ohms are 330 passes test
B) check between pin 7 and 8 ohms are 790 passes the test.
C) check between pins 8 and 9 ohms are 210 passes the test.
According to every thing I can read the issue is not in my injection system.

I have good spark, I have tested the ignition system 3x, will do a 4th time, but unlikely my readings will change. Good fuel, good spark engine should go vroooooommmmmm. Any new suggetions?