lw300 needed a tow

Stopped at a light the other day on the way to work and the engine sputtered and died. Wouldn't restart even with the MAF unplugged (causes a limp-home
mode).
Towed to a shop (I'm on a deadline at work so couldn't futz with it myself) where they finally got it to start. It sounded like the ignition would cut out intermittently at idle when hot. Wound up throwing a new crank angle sensor in it and so far, seems to be running well. As a test, when it died initially, I had put a bit of sheet metal under the EGR valve to block it off since I was thinking that it hadn't been closing properly and giving me other issues. Block-off is still in place and check engine light is on though displaying only EGR related issues. Without EGR, the knock sensor will just cut back the timing so no destructive pinging that I have to worry about for the moment.
Figure if all is well, in a few days will pull out the EGR valve to inspect and replace if necessary.
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Oppie wrote:

Sounds like my old 89 Mustang. The electronic ignition module was the cause there. I had a 79 Datsun once. The first thing I did was the sheet metal thing for the EGR after the guys at my old job said EGR was like throwing water on a fire. That car ran perfectly for over 200k miles until rust did it in! Even passed emissions every time with flying colors. Of course the engine was only 1.2 litre.
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Looked up the EGR valve in the factory service manual. I had thought it was a motor operated pintle valve but it turns out that it is a solenoid with a position feedback pot. Should be able to energize the pot on my workbench with 5V, measure pot voltage with a meter and push the valve manually to see if the pot has any dead spots. Not sure what the return spring tension is supposed to be and if the valve is being jammed by carbon. Will have to look further into this. Don't want to be spending on unnecessary parts.
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Found there is something wrong with the airflow calibration when the engine is hot. Replaced the MAF in December and seemed to make a difference for a while. Check engine light stayed off long enough to pass state inspection.
This engine will work perfectly well with the MAF disconnected. It just runs a bit more rich. Friend at the repair shop said that if the engine won't start, disconnect the plug to the MAF, turn the key to on for 20 seconds and then start. On the few times it's been finicky since, this has worked. Still want to find the root cause...
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