I have bypassed VATS key with proper resistor. Bypassed the VATS starter relay module with jumper wire, although not sure how great my jumper wire spade connectors sit in the relay receiver plug. [i may cut the 2 outside relay wires and use a butt connector to be certain...just hate cutting factory plug like that.... I cringed cutting VATS ignition plug for the resistor...but there is enough wire to splice back in].

Car always starts great when it hasn't been used for days, even an hour after use it always starts. HOWEVER, I have had 4 occasions where i shut off car and it won't crank, start, nothing. No click sound; just dead. Wait an hour or so and it starts. First couple of times this occurred after driving about an hour. The more recent 2 occasions it was short trips, 15 mins of driving. Doesn't happen all the time. Whenever I shut off, i try to re-start just to see how it's behaving. Almost always re-starts like there is no issue. BUT then the ugly Gremlin rears its head!

1989 with 18,000 miles. Always garaged, no corrosion issues. Checked all grounds I could find, battery cables tight, don't appear corroded. If it was cables or ground I would think this issue should be more frequent and wouldn't somehow fix itself from sitting 1 hour. When this first happened about a year ago I re & re starter but the replacement wouldn't work; I think the pinion gear didn't push out far enough to engage flywheel because replacement starter bench tested fine. I also read lots on these forums saying keep the OEM Denso, so i did. Still has the OEM starter.

is it possible the starter could be a little sticky at times and not push out pinion gear, or perhaps flat spot on motor? Not sure how this would fix itself after sitting an hour.🤷‍♂️

Also wondering about the ignition? Not sure what takes place when I turn a key forward to send signal to engage starter but could this be my culprit?? If i shoot electrical cleaner in the ignition will it help??

thanks for any insight!!

 

I had the same issue for two years, always drama when getting gas......will it start or not. After my starter was rebuilt, still had the issue. It was not VATS so must be the clutch safety switch. Found the switch under the dashboard, followed the connector and jumped it. Now no more drama and she fires off immediately! I am the only driver so putting car in neutral or pushing clutch to the floor before starting is not an issue since the safety is now gone. She will jump if you turn the key with gears engaged. Good luck and keep us posted.

 

You could wire a bulb to S terminal on solenoid and zip tie it to ac plumbing. When it doesn’t crank, you will he able to see if it’s the starter or ignition related.

 

After checking the clutch safety switch, or neutral safety switch if you have an automatic,Id stress test the battery and disassemble the grounds and connections and clean them. Even though they are tight there may be corrosion present.You may want to take a closer look at your solenoid.

 

mine is Auto. I also wondered about neutral safety switch. When it acts up like this, i always put it in neutral as well to see if it will start. Not sure if putting it in N changes a neutral safety issue. Good point and a good place to check. Too funny Dredgeguy...i think exact same thing at gas pump and one of my no-starts was at pump and I had to push it out of way in N. That is actually when I learned about VATS starter relay. heard it click while I was waiting for rescue and then it fired right up. When I bypassed that I thought I was all good.

Just did some searches and someone posted the NSS on these rarely fail. My low mileage a consideration? it seems like the brass contacts wear out which would seem usage/wear & tear related.

 

This sounds like a classic solenoid "heat soak" issue. During operation the starter is heated by proximity to the engine block, pre-cats (1989), and general engine compartment airflow. When electrical conductors heat up, resistance goes up. Higher resistance reduces current flow, and the solenoid coil can't pull in the armature to close the motor contacts. Generally you won't hear anything, but there may be an indication of voltage draw by a slight dimming of courtesy or dash lights. Slight.

Watch for the indication of a slight system voltage drop. If it occurs, it is the starter itself.

 

thnx IHBD. The very first time this happened I thot of heat soak, which is why I ordered replacement starter. my last 2 occasions have been after short 15-20 minute drives. it is very unpredictable and random. I can drive 1.5 hours, no issue, or 15 mins and it acts up. If it was a heat soak issue, I'd expect to be more frequent and after longer drives. 🤷‍♂️

 

I've had a similar issue on my C4 and C5 that gradually happened more often, was very sporadic. Both times it was the starter, then also had a similar situation on C5 that was fuel pump related, it turned out the fuel pump was not running because the BAP (boost a pump) was failing. The BAP related one happened more often after I would drive it VS cold, but finally no start at all. I had my clutch switch go out too on C4, but that seemed to just go bad and no start. The weird thing was I was replacing my slave/master and it worked prior, then it failed, probably because all the clutch pumping.