H2

Some of you may remember that I had been experiencing a no-spark problem and offered a $100 reward to the person/s who helped me the most in diagnosing and fixing the problem. There actually were THREE people who submitted information that, together, helped me zero in on and fix the no-fire problem on my 968 by providing important and well thought out ideas and details on how to troubleshoot. Between the three of them, I was able to get the car running so I’ve decided to divide the reward. The Winners were SoCal968 ($25), Greimann ($25) and Brett968 ($50, since Brett968’s detailed posts and PMs were the closest to what I needed and quickly put me onto the fix). Brett gave me the most explicit how-to directions in easily understandable terms (for a dummy like me). Many others submitted information that helped eliminate very possible problems and would have helped me get to the resolution eventually but I’d probably still be out in the garage tinkering and trying to figure things out. I’m not the brightest crayon in the 968 electrical box. Obviously, we don’t need to pay for information on sites like these but I was in a bind and I did want to reward them for their willingness and patience in sharing information. Many people made other useful suggestions along the way that were very helpful and I learned a lot about the 968 in a relatively short time. I can change a reference sensor in the dark now.

WHAT WAS THE PROBLEM AND FIX? The DME was not getting power and it appears that it was either the alarm blocking power or a /bad pin connection that I inadvertently fixed while checking the different DME pins out and making sure they were clean. The car had been sitting a couple of months in damp weather, and I had a rear hatch leak and a small battery tray water leak, so it’s conceiveable that moisture had messed up a connection with corrosion. I traced the DME/Alarm system wiring and connections (and replaced the alarm with a spare I had on hand) tightened up and cleaned all connections that had specifically been pointed out...and the car started up immediately and ran great. Verifying that the DME was not getting power, the symptoms of a non-operational DME, and precisely where to look and how to check was really helpful in narrowing things down. Unfortunately, I'm not exactly sure what the precise magic bullet was but I followed all hints and carefully used Brett968's meticulously thought out directions, in conjunction with Greimann’s pin-out diagrams and suggestions, and SoCal968's very helpful and guiding recommendations. Using the three together, it all came together. I'm horrible at reading electrical schematics but this did the trick. Thanks to all! What great music it is to hear a engine fire up after several months of not firing.

I had 12V power to the coil and the injectors but no spark to the plugs and no electrical pulse to trigger the injectors to work. The fuel pump worked when jumpered but not when trying to crank with a new DME relay in place. I checked and cleaned all major grounds, all connectors, replaced with new parts the coil, distributor, plugs, rotor, reference sensor, coil wire, several relays, fuses, even tried a spare DME brain…nothing made a difference. I couldn’t read the Check Engine Light (CEL) fault codes because that light is powered by the DME (but the other dash lights DID come on causing me some confusion). Now the CEL light works and the fault code is 1-5 (all OK). BTW, after I got it running the CEL light would not go out so I killed the engine, pulled the battery leads, waited a few minutes, hooked them up again and cranked and the CEL light lit up briefly and went out like it’s supposed to. I was concerned that it might be a broken wire in the wiring harness as one wire had been pinched slightly in the tbelt/roller/waterpump changout and Cam Tower removal to check the cams. That coax cable would have been a bear to splice!

Many of the new parts I bought I was going to replace anyway although much of what I replaced doesn’t look very old but I don’t have a good service history on the car and I’m more comfortable keeping the old parts for spares and running on new wear parts. The
shotgun approach at replacing parts cost me $500 plus, and I spent FOREVER troubleshooting the problem, and it turned out to be that the DME was not getting power, apparently due to a bad connection (or bad alarm). Check your battery tray. Mine looked pretty good but I easily punched screwdriver through the bottom = seepage.

Some bypass the alarm to check continuity through it but I had access to a used one and just put it in, cleaned pins, tightened connections, etc. Then it started easy as pie. Scares me a little in that I'm not positive what the precise fix was. The small water leak from the battery tray (over the DME) probably contributed to some corrosion and a pin not making good contact.

Now that I’ve learned a few things, perhaps I can repay others on the list by sharing my limited experience. BTW, when the engine started running, I was losing oil from the front crank gear seal. I’d replaced it but the replacement part sent to me by the vendor was a different part number than what I took out. Sooooo…I had to tear the front of the engine off again (only 1 hour this time instead of many). Tomorrow I’ll order new seals and put the belts/seals back on again, assemble, and hope it cranks up!

968…what a car!