scotsman60

Laura,


The distributor belt is good. I check it every few months.

The car also runs with either distributor disconnected so I'm pretty sure I don't have a distributor problem. I will be checking (tonight) to make sure that the belt hasn't jumped a tooth though - although this wonlt affect ignition timing unless it's jumped several teeth it may reduce the spark efficiency.




Doug

jonfkaminsky

Hi All-
Time to bump this thread as it contains a lot of information, and it is my opinion that these sorts of problems are on the upswing due to relative age of our cars.

Re my personal issue, I have not solved it yet. I recently replaced both disty caps and rotors. Upon inspection of the worn parts, it seemed clear that these needed replacement anyway....

I went for a drive, the engine temp read to the quasi-horizontal line, and returned home with the CEL on. I read out the fault codes which were the usual 1134 (Hall Sensor), and two additional which may or may not have been there before (1254 and 1255) for intermittent injector failures.

I cleared DME, checked the resistance value for the cylinder head temp sensor (was in spec) per Adrian's book, and went for a drive. Idle was markedly cleaned up with the new parts, and I thought I was home free until about 10 minutes into it, all the dash lights came on and the chime started sounding. Engine was running hotter than usual for the outside temp as well. No pinging but I had a tank full of jacked up fuel.

Checked the DME relay per Adrian's book - car starts/runs with the jumper wire installed.

I went ahead and purchased the cylinder head temp sensor anyway and will try to fit it this weekend as soon as I find a way to grind down a socket to install it.

I guess all I have left for the low-hanging fruit is to replace all the plug wires. I am also going to pull the ignition wires at each coil amplifier and see it there is a difference between the banks of spark wires.

Anyone have additional ideas? Loren? Adrian? Beuhler? Anyone? Anyone?

I would sure appreciate solving this problem as the car is fairly undrivable now with the dashlights on and the warning chime sounding.

Thanks!

Jon

Adrian

Dear Jon,
Personally I would be looking at the engine loom connectors and wiring. This problem seems electrical to me rather than sensor component related.
There have been a number of cases (especially with cat removals and replacement with bypass pipes) of exhaust gas damage to surrounding wiring and connectors. I would certainly advise that you remove the cover to the engine bay electrical panel and check those connectors in there both the engine side and the car side.
Have you checked the ignition switch?
Ciao,
Adrian
964C4

Lorenfb

"I thought I was home free until about 10 minutes into it, all the dash lights came on and the chime started sounding."

It's not clear what your problem is. Do you have a consistent problem or is it random/
intermittent. The one above can result from a low battery voltage (bad alternator).
Don't waste time and money on the temp sensor if it measures correctly. You're
correct in assuming bad plug wires are the source of problems for a poor running
condition. You can isolate the upper and lower wires by just disconnecting one of
the two ignition modules.

Try and get a better understanding of the problem.

jonfkaminsky

Okay thanks guys. Loren - I have not checked the temp sensor throughout all possible ranges - just the hottest. The problem seems intermittent but never shows up until the car is warm - and if cold enough, I may get away for a day without seeing anything. Didn't see anything this morning for example and it is quite cool today. I got it up past the horizontal temp mark and then it came rapidly back down to normal range. I used to never get it about that line on cold mornings.

I registered a 1234 fault code last night - but the intermittent injector faults were gone.

Adrian- I have been all over this car using your book and Rennlist notes when possible checking electrical things - I cannot find it. I have checked the ignition switch by manual methods - it seems intact.

This morning, I disconnected the ignition modules one by one near the amplifier/coil area. The module further toward the front of the car had little effect. WHen I pulled the rear module (toward the rear of car) it had a noticeable effect on the idle RPM and smoothness. Mean anything?


Jon

Adrian

Dear Jon,
This suggests a problem in the still active ignition system. Trace the wire from the disconnected unit to its distributor cap to see which one you actually disconnected. I am reluctant to say primary or secondary because I have seen both coils hooked up either way.
Swap the coils over and see if the problem is the same. This eliminates the coil from the problem. Careful you do not confuse yourself.
Ciao,
Adrian
964C4

jonfkaminsky

Dear Adrian-

Here is what happened when I went back to try your suggestion. As is, the rear coil was connected to the primary distributor (the lower one) and the coil toward the front of the vehicle was connected to the secondary distributor (higher, nearer center of the engine). I switched the connectors and the poorer running result followed the connector ...i.e. the distributor cap. In other words, when only the primary distributor was connected to either of the coils, the engine ran poorly in comparison to when only the secondary distributor was connected.

Have I then taken the coils out of the equation? Since the caps and rotors are new, would perhaps my next step be replacement of the spark wires? AFAIK, they are original. If so, can you recommend a nice set?

Thanks,
Jon

jonfkaminsky

Yeah...shameless bump....

:-)

Adrian

Dear Jon,
I am not quite with your description of the distributors. The primary distributor is the larget part of the assembly. It is the one with the connector sticking out of the side of it.
Your test does eliminate the coils. It would suggest either a set of new spark plugs is needed or some leads need testing using a proper ignition lead tester.
A set of spark plug leads is VERY expensive. I do not have any aftermarket recommendations because I used originals from PAG.
The only thing for me is confirm you have the primary and secondary distributors around the the correct way. Deepest part of the assembly is the primary and the shallow part is the secondary.
Ciao,
Adrian
964C4

Lorenfb

"Have I then taken the coils out of the equation? Since the caps and rotors are new, would perhaps my next step be replacement of the spark wires? AFAIK, they are original. If so, can you recommend a nice set?"

Use an ohmmeter to check each wire and spark plug connector. Also, I've seen where
very high mileage spark plugs caused a poor running problem. You need to do a more
extensive troubleshooting. These problems are just not that simple to locate as
switching a few parts and can result in wasted parts purchases if done incorrectly.

jonfkaminsky

Adrian-
perhaps my nomenclature was incorrect, but the description of the placement was not. Before I unplugged anything, the rear-most coil was connected to the the lower distributor and the coil toward the front of the vehicle was connected to the higher distributor (nearer to the center of the engine), which as you point out, is the primary distributor.

Thanks for your careful reading,
jon

jonfkaminsky

Just an update - after the replacement of the spark plugs, plug wires, dist caps and rotors the engine is running quite well and have not seen any check engine lights in a couple days. I believe this has solved the majority of the problem.

The motor is still running a bit hot which seems to be possibly related to the oil cooler fan not coming on. I can jumper it and make it come on at high speed, but still not clear whether it comes on a low speed and at the proper time.

Randall G.

That's great news, John! Though, "solved the majority" sounds a bit discouraging....

Wrt to the oil cooler fan, does the slow-speed fan work when jumpered?

Since this thread has been bumped, suppose I'll use this an opportunity to correct bs I wrote earlier (way back) in the thread = my mechanic used a rubber mallet to check the knock-sensors. Don't know what I was thinking when I typed that--he used something like a screw-driver (metallic), which makes way more sense than a soft object, of course. I went ahead and edited my old post.....

jonfkaminsky

Hi Randall-
Great troubleshooting document!

The relay test confirms nothing wrong with the ballast resistor. Both low speed and high speed work. I switched relays with the AC and unless something is wrong with both, there was no effect.

The car temp gauge used to run up to just below the second line, then take a dive and sit halfway in between the low line and the 9:00 pm line. Now the temp guage rises slowly to above the 9:00 pm line and pretty much hovers around 9:00 pm no matter what.

Based on the sound coming from the fans when I did the relay test, and from what I remember as normal sounds sitting in traffic, I would say that fan is not coming on at all.

Jon

Randall G.

Thanks for the kind words, Jon.

If your A/C condenser fan continued to run in slow-speed with the A/C on, the slow-speed (internal) relay is working okay.

Your next step is to test (or simply replace, since it's easy and cheap) the temperature sensor on the oil cooler.

Talk to ya' soon.....