My Sh1t is teh broken (no fuel or spark)

[jckrieger]

Ok, I was on my way to the SDAC-Chicago meeting today in my 87 CSX when all of a sudden the car lost all spark and fuel. As the car slowed to around 30mph, the engine fired back up after a loud backfire and continued to drive. This loss became frequent enough that I turned around and headed back home, but it got so worse that I would have to let the car sit on the side of the road before it would fire back up.

Any ideas? I'm thinking it might be the HEP.

Oh yeah, no codes and the check engine light operated normally when the motor wouldn't run.

[dwh4784]

I'd guess HEP first but the ASD relay might be freaking out for some reason. I remember once my friend pushed the wrong button on the OTC scanner and it tripped the ASD relay while driving 55mph, it was doing what you describe and wouldn't start until it sat a few minutes.

[altered7151]

That does sound alot like a ASD problem, although it wouldn't hurt to try swapping out the HEP, that is of course if you're like me and keep a few laying around just in case.

[jckrieger]

I have piles of HEP's laying around, so I'll replace that first. The ASD relay isn't a bad idea, but I can hear the fuel pump prime sometimes even when the car won't start. Wouldn't that mean the ASD is probably ok? I'd replace the ASD relay, but isn't it in the power module somewhere on the 87's?

[GLHSKEN]

Yes, The ASD is in the PM for 87's. Check the grounds Clark, especially the one's on the pass side engine mount and from the 2 piece to the firewall.

[jckrieger]

Ok, I read the codes again today and now I'm getting code 54 (HEP). I replaced the HEP and the ignition coil (I had plenty of spares) and I'm getting exactly the same behavior. All grounds are in place and making a good connection (no rust and the headlights/stereo function properly). I looked around at the wiring harness by the battery and found 2 wires that had been partially chewed and are now broken due to corrosion.

Now for my next question:

I have an 88 T1 P body wiring harness with 27K miles on it sitting in a box somewhere. Will all the connectors mate up behind the firewall? If so, I'll just trash this CSX harness and convert the car to SMEC since I have piles of socketed SMECS laying around. Let me know what you guys think.

Clark

[turbovanman²]

Its quite possible your used HEP is no good. I found that out the hard way too. My HEP went, swapped in a used one and it kept cutting out, finally bought a brand new Mopar unit and its been fine. I have a known good spare I keep in my van, just in case, :thumb:

[BadAssPerformance]

I have an 88 T1 P body wiring harness with 27K miles on it sitting in a box somewhere. Will all the connectors mate up behind the firewall? If so, I'll just trash this CSX harness and convert the car to SMEC since I have piles of socketed SMECS laying around. Let me know what you guys think.

Clark

An amazing amount of things changed in p-bodies between '87 and '88 so I wouldnt bet that they are identical... if they are tho, and you SMEC it up, I'd like to intercept that '87 harness on the way to the trash.

definitely try another plate or two first tho...

[Skibbe]

Alex's first GLHS was acting like that... I remember pushing him through intersections with my neon. He'd sit on the side of the road for awhile, and it would fire up and take off again. Next time he go stuck at a light we'd repeat the process.

His underhood power module was overheating... this was after he moved it away from the air duct next to the headlight. A small computer fan mounted to the power module solved the problem.

Don't know if you've moved the power module around or not, but its another component to swap.

[BadAssPerformance]

Yeah, I remember that... we put that same PM in the NYer and it did the same thing when the computer fan died in the 106F track temps at SDAC-13...

[jckrieger]

Ok, the power module thing makes some sense. I've seen animal nests built up in the computers before, and I've never had the power module out of this car. The car has had a lot of mouse destruction, so I woudln't be surprised if something was getting a little warm. The only problem I have with overheating is that the car still didn't want to run consistently when it was cold today, though I may have done permanent damage to the module. The power module shouldn't be overheating, but I did notice I used the wrong hose that connects the airbox to the power module so it's not sealing very well (there's about a 1/2'' gap).

As far as the HEP goes, I first tried a random used HEP from a parts motor, but then I tried a known good HEP from my old Shelby Charger race car. I figured since the car behaved the same way with all 3, it's probably not the problem.

Since Peter still hasn't picked up my 87 Daytona, I might switch power modules next time I'm at the car to see if that solves the problem. The only other thing I can think of is the capacitor on the ignition coil might be shot (my old lawn mower woudln't run without it). If the power module doesn't change things, I'm going to pull the engine harness and either make repairs to it or just swap the whole thing out.

[jckrieger]

Well, I totally went through the entire wiring harness and fixed all the frayed/broken wires and replaced any questionable fusable links with replacable fuses. After I put the harness back in and went to start the car... same thing as before. I'll swap out the power module on Monday or Tuesday and see if that fixes my problem. I would have done it today, but my friends got their trucks buried in the creek and I had to dig them out with the track loader.

[jckrieger]

Tonight I swapped in the power module from my 87 Daytona and drove the car 30 miles home with the only problem being a code 24... which I will decypher later. So, is there anyone out there, preferably in Chicagoland with a spare power module?

[turbovanman²]

I have one, $60 shipped. :thumb:

[jckrieger]

I think I found one pseudo-locally... for the price of gas :)