89 running fine just died while idling

Had not driven my 89 for about a month, so just started it up today to let battery recover. Started fine, no malfunction msgs. Ran idling for about 5 minutes and just quit; turns over fine but like not firing at all. Any ideas suggestions?

Thanks

If it had run long enough to get hot, I'd suspect the ignition control module. Seems the most common cause of spontaneous shutdown on 88-90 models as the Magnavox module is known to do this after is spews the green goo. Thermal (heat related) failures are a hallmark of these modules when the get old.

Could be failure of the crank position sensor though that usually coincides with a breakup of the harmonic balancer. The noise alone would probably tip you off if that had happened.

All that said, basic trouble shooting will be in order. Check for spark, if that is present check for fuel at the rail. If those are both ok then can start looking for trouble with various modules and the like.

KDirk

I disagree with mssr.Dirk as to crankshaft position sensor failure; these sensors fail on their own accord, no mechanical involvement. The CPS is my FIRST suspect with this symptom; fuelpump second, ign. module third.

I had that exact same situation happen on the Black. Harmonic Balancer works/looks great, Crank Position Sensor broke. Had it towed to my mechanic friends house and he diagnosed quickly and replaced it.

Thanks everyone. Any simple way for me to check the crank sensor without having it towed to garage? Can I even get to it; where exactly is it located? Checked for codes thru crt; only one was a history of cm553??

Have to pull the harmonic balancer; no easy task.

No code will set.

This test should tell you if the crank position sensor is working.

Disconnect the oil pressure sensor.

Connect a volt meter lead to the green fuel pump test/prime connector and the other lead to ground.

Spin the engine with the starter while you observe the volt meter. If your meter reads 12 volts while the engine is spinning the crank sensor is probably good.

oil pressure sensor

if you don't have a "Factory Service Manual" for your '89, it's time to get one.

while i prefer a "hard copy", one is available online for free: http://reatta.net/docs.html

it may take a couple days to get your password info. i'd give you mine, but apparently that can get me "suspended" or "banned" from the forum...

changing the crank sensor is quite labor intensive - aka: a pita!:eek: the smallest cracks in the crankshaft (harmonic) balancer - with enough light - you should be able to turn and see the front of the balancer while on the engine. the rear side is much harder to see.

if it does turn out to be a crank sensor problem, i'd also replace the balancer, since it's probably 25 years old now, and will crack soon - if it hasn't already.

i wouldn't rule out what Kevin said in post #2 and just saw that Ronnie posted another check.:cool:

while my balancer and crank sensor were bad, my fuel pump was also intermittent. check your fuel pressure - it should be around 42psi or so...

Ref shop manual; thanks for password offer. I have used reatta.net/docs and have login id and passwordd. Hve kept 89 going since 1997 with help of all you great forum folks but think this is over my head so looks like time to have it towed to shop. Thanks again. Will respond when diagnosed/fixed.

All is good again. For those of you who suspected crank sensor, you were right. Had towed yesterday morning and was a-ok by lunch time today. Tech said balancer looked great so got sensor replaced and new serpentine belt for not too big a strain on wallet. Thanks again everyone.

thanks for the update!:cool: