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Hi all,
I have an 88 900s, 80k that has randomly failed to start on occasion. After some equally random period of time, it restarts beautifully and resumes normal daily operations.
When it fails to start, there is no fuel pump sound, though the pump can be made to work with a known +12vdc. (I use the rear window defroster as my supply for testing) I have not yet gotten to check for spark.
Related (or not): A very reputable indie shop replaced the ECU in July when the previous owner had a "Failed to start" problem. Then it failed to start in the middle of my inspection for purchase.* The shop put in ANOTHER ECU under warranty (told you they were good) and we enjoyed peace and happiness for months.
Last failure to start was yesterday, before that about 2 weeks.
I was advised on my previous thread by RS:
"When they changed out the ECU, did they change the system relay and fuel pump relay. These are located above the ECU, on the right side."
I don't know about the replacement, but there are no relays on the right side of the engine compartment, nor to the right of the ECU. (ECU's on the left, on the tilt-and-remove rack, above the cruise control and next to the spark-module. Right? The only relay I can find in the engine compartment is in this area, but if I pull it--to clean terminals--it has no effect on the engine's running.)
"Townsend imports mentions that, when you change a failed ECU, you really should change those relays. As the relays get old, the "snubbers" on them tend to die and, when the ECU de-energizes the relays, they backfeed current to the solid-state relays in the ECU as the magnetic field in the relay coils collapse. This tends to damage the solid-state ECU relays."
This makes excellant sense. Except I've been searching the Townsend site and I cannot find this reference.
If the kind reader could direct me to these relays, I will not only happily replace them, I'll add new capacitors to the circuit: Analog computers fail rather hastily from unfiltered relay noise.
And if the reader has another favorite suggestion, please by all means lemme have it. I'm in a spot of trouble here as the weather's getting a tad nasty for walking home. (The Haynes manual's great for me, but my wife's not too happy about learning to read those diagrams and use a voltmeter...)
Thanks
Ben
*Yes, the car failing to start should've been a show-stopper. Two things: NEVER buy a car on eBay. And I buy cars like Charlie Brown buys christmas trees. Ask me about my 9000...
posted by 64.81.14...
, Sat, 14 Dec 2002 16:17:15
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