'84 928s auto starts and stalls instantly
01-21-2015, 05:01 PM
#16
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just jumper the coil small + terminal from the jump start post that gives it a full 12 volts....do not run it long that way as it will cook the coil...but will confirm that it is NOT the resistors ....
And yes Tom I would have taken that bet...besides we should have lunch one of these days. Right now trying to fill two truck loads of cars .....got 9 need 3 more.
And yes Tom I would have taken that bet...besides we should have lunch one of these days. Right now trying to fill two truck loads of cars .....got 9 need 3 more.
Anytime you are in town I will spring for lunch.
Been way to long.
Tom
01-30-2015, 10:46 PM
#19
Intermediate
Thread Starter
So many fixes seem to involve grounding...
When I get back in the garage, I'll make it a point to track that down as well as the other suggestions that have been made. Sorry I haven't been as motivated to fix my toys as I used to be. I just HATE F****n winter! (pardon my censored French) I did buy a better multimeter that I'm looking forward to using as soon as it gets above freezing in my garage. As we get older and have more horses in our stables, you only need one or two that you have to count on. 
02-16-2015, 07:09 PM
#20
Intermediate
Thread Starter
package from 928 intl. on the way...
I decided to replace the coil and both ballast resistors. Won't be able to do anything w/ my left hand for a while.....have right hand fingers crossed that this'll help!
04-01-2015, 07:26 PM
#21
Intermediate
Thread Starter
Had enough recovery in my left hand to...
....install 2 new resistors and a different good used coil. No difference. The shop manuals have a very thorough flowchart of diagnostics. I'll pursue that soon.
04-01-2015, 09:55 PM
#24
Race Car
Check your AFC relay and fuse first.
As previously mentioned get a node lamp, auto stores rent them for free. Your start then die is most likely showing you the cold start injector is working. The noid lamp will confirm that injectors are firing.
There are two grounds located on the pass cam covers on an 82 not sure about your year, that you need to make sure they are are clean.
if injector connector has been twisted when removing the insulation can break off under the rubber boot, one short takes them all down.
Test by removing all injector connectors pick an injector measure across the two pins it should read open.
https://rennlist.com/forums/928-foru...blown-out.html
As previously mentioned get a node lamp, auto stores rent them for free. Your start then die is most likely showing you the cold start injector is working. The noid lamp will confirm that injectors are firing.
There are two grounds located on the pass cam covers on an 82 not sure about your year, that you need to make sure they are are clean.
if injector connector has been twisted when removing the insulation can break off under the rubber boot, one short takes them all down.
Test by removing all injector connectors pick an injector measure across the two pins it should read open.
https://rennlist.com/forums/928-foru...blown-out.html
04-02-2015, 11:24 AM
#25
Three Wheelin'
Check your AFC relay and fuse first.
As previously mentioned get a node lamp, auto stores rent them for free. Your start then die is most likely showing you the cold start injector is working. The noid lamp will confirm that injectors are firing.
There are two grounds located on the pass cam covers on an 82 not sure about your year, that you need to make sure they are are clean.
if injector connector has been twisted when removing the insulation can break off under the rubber boot, one short takes them all down.
Test by removing all injector connectors pick an injector measure across the two pins it should read open.
https://rennlist.com/forums/928-foru...blown-out.html
As previously mentioned get a node lamp, auto stores rent them for free. Your start then die is most likely showing you the cold start injector is working. The noid lamp will confirm that injectors are firing.
There are two grounds located on the pass cam covers on an 82 not sure about your year, that you need to make sure they are are clean.
if injector connector has been twisted when removing the insulation can break off under the rubber boot, one short takes them all down.
Test by removing all injector connectors pick an injector measure across the two pins it should read open.
https://rennlist.com/forums/928-foru...blown-out.html
04-30-2015, 11:52 PM
#26
Intermediate
Thread Starter
I haven't completed the full troubleshooting process outlined in the factory manuals, but I HAVE ruled out the grounds, relays, fuses, temp sensors, and plugs. The one thing I have a major suspicion of now is the MAF sensor. I have the model # 0280 203 015. The resistances are close to spec, but.....if there's supposed to be a heated wire in the inlet, there isn't. Just a small white plastic protrusion, about half the size of a Bic pen cap. it feels like there's a hint of a wire at the tip of it, but nothing extends beyond the plastic. Thoughts, anyone? I can't find anything definitive that tells me this is damaged, but I suspect it is.
04-30-2015, 11:59 PM
#27
As someone who's fought this several times on these, I've had several that were the result of bad starters. Now you might say "Dafuq is he talking about" and you'd be right to say that.
Take a look at the starter and you will see 3 pin outs and one of those acts as a signal to the resistors. Turn the key on and see if the resistors are getting hot, leave the key on, don't try to start. Do they? If so, you have a problem on the starter. If they don't, ignore what I'm saying
I've got one here from a few states over and all the shops there couldn't figure it out. I tossed in a new starter and it fired right up. The results of having a car that showed up here 3 years back with no fenders, most of the interior gutted and it was one that most would have written off. I put all the wiring back where it should be and it still did this same thing. Put in a newly rebuilt starter from Roger and same thing. Pulled a spare starter off the shelf and tossed it in and damned if it didnt' start right up. Apparently one of the requirements on rebuilding the starter isn't making sure that 3rd post does what it should. The one I did this week had the same issues and it had a rebuilt starter from Pelican Parts (it was two years old on the purchase so I used it as a core). Rebuilt from Roger cured it.
Don't be quick to discount what you did already.
The car with no fenders? It's been rebuilt completely with new paint, new Rob Budd interior and is now a damn near show winner.
Take a look at the starter and you will see 3 pin outs and one of those acts as a signal to the resistors. Turn the key on and see if the resistors are getting hot, leave the key on, don't try to start. Do they? If so, you have a problem on the starter. If they don't, ignore what I'm saying
I've got one here from a few states over and all the shops there couldn't figure it out. I tossed in a new starter and it fired right up. The results of having a car that showed up here 3 years back with no fenders, most of the interior gutted and it was one that most would have written off. I put all the wiring back where it should be and it still did this same thing. Put in a newly rebuilt starter from Roger and same thing. Pulled a spare starter off the shelf and tossed it in and damned if it didnt' start right up. Apparently one of the requirements on rebuilding the starter isn't making sure that 3rd post does what it should. The one I did this week had the same issues and it had a rebuilt starter from Pelican Parts (it was two years old on the purchase so I used it as a core). Rebuilt from Roger cured it.
Don't be quick to discount what you did already.
The car with no fenders? It's been rebuilt completely with new paint, new Rob Budd interior and is now a damn near show winner.
05-01-2015, 08:01 AM
#29
Does the car run on ether? Maybe I missed it in a post or something, but have you ruled out a fuel issue? The pump should run for a few seconds when you first turn the key, and continue running if the CPS, crank sensor, sees rotation of the crank.
Just wondering if it could be a fuel supply issue. Looking forward to finding out the problem, since I have a 84 also.
Brian.
Just wondering if it could be a fuel supply issue. Looking forward to finding out the problem, since I have a 84 also.
Brian.
05-01-2015, 01:24 PM
#30
Intermediate
Thread Starter
No, the fuel pump has apparently been wired to bypass the pump relay. It runs continuously., even without the relay in place. I've also determined with a noid lamp that the injectors on either bank are not firing. As someone had already guessed, it seems that it's only running for a couple seconds solely on the cold start injector.