If it's over 80 degrees outside, my ETA won't start

[RoyalW/BlauCheese]

This is a weird one. My 1987 ETA wil crank but won't start if the outside temperature is above 80 degrees Fahrenheit. I tested spark plugs and my internal fuel pump works. My outside fuel pump is loud as hell though. My ICV needs to be screwed to the lowest idling position for my car not to idle above 1000 rpm.

I'm currently stuck in a parking lot writing this haha

[Balleristic31]

Main symptoms are high idle (~1500 rpm) before no restart, no spark, and when it finally does start it has weak orange spark.

[Best_name_available]

This happened in my old is, turned out to be the CPS, it just did not like it when hot. actually my current is will hesitate on really hot days as well, I'm almost positive it's the CPS as almost everything else has been refreshed.

[dnguyen1963]

CPS is a magnetic sensor. Temperature should not have any effect on it. The wiring connecting the CPS might be a different story, but my bet is on vacuum leaks.

[Kershaw]

Vacuum leaks would not create a no spark situation. CPS definitely would do that. High idle usually means vacuum leaks though.

I would definitely test the CPS, and once it's running again. Park it and do a smoke test.

[Cephas]

CPS is a magnetic sensor. Temperature should not have any effect on it. The wiring connecting the CPS might be a different story, but my bet is on vacuum leaks.

Correct in that it is a magnetic sensor, but I know from experience that they can fail under warmer temps.

OP, my ETA did something very similar. It would die on me after driving it for an extended period. Turns out that the Engine Speed Sensor and the Crank Sensor (ETA's have both) needed to be replaced. The speed sensor would drop signal when it was warmed up. This was confirmed by a bench test and once replaced, I never had the issue again.

Good luck!

[jeffnhiscars]

This is a weird one. My 1987 ETA wil crank but won't start if the outside temperature is above 80 degrees Fahrenheit. I tested spark plugs and my internal fuel pump works. My outside fuel pump is loud as hell though. My ICV needs to be screwed to the lowest idling position for my car not to idle above 1000 rpm.

I'm currently stuck in a parking lot writing this haha

Loud external fuel pump is often a sign of a failed in tank pump which forces the external to suck rather than push. This causes cavitation i.e. Air bubbles in the fuel which, while not directly tied to heat, could be causing a form of vapor lock.

That's my esoteric diagnostic BS for the day :)

[RoyalW/BlauCheese]

I'll check the cps and engine speed sensor. I tested my in tank fuel pump and it works. Maybe it just isn't working hard enough? I'll smoke test it and will probably have some leaks(my luck). I'll keep you guys posted. Still open to other suggestions tho

[Kershaw]

Loud external fuel pump is often a sign of a failed in tank pump which forces the external to suck rather than push. This causes cavitation i.e. Air bubbles in the fuel which, while not directly tied to heat, could be causing a form of vapor lock.

That's my esoteric diagnostic BS for the day :)

That happened to my e21. The fuel accumulator was bad so when you turned off the car, the heat would vaporize the fuel and vapor lock the engine. Only after an hour or so would the car start, after being turned off.

[Best_name_available]

If I still had my extra I'd come down and help you, didn't realize you were so close

[RobDog]

I have had both a no spark when warm and another no spark when cold situations with my dad's 87 eta (I really hated this car for the first 6 months). The no start when warm would happen if the car was in the sun to long. The car would just crank forever during the day, but start up and run great at night when it was cool outside. That problem ended be the ECU. Swapped for a good ECU and the problem went away.

The no start when cold was a weird one. The car would not start with the starter (but would crank). The only way to get the car running was to push start the car. Once warmed the car would start with the starter. This problem ended up being the engine speed sensor. The sensor would olm good but was bad, making finding the problem a bit harder.

[whitebulat22]

I had a similar issue because of the main relay. Surprised me after running perfectly to get lost and stranded in a remote area far from home, but was picked up and driven in the morning when it was cooler. Never again will I drive an E30 away without a brand new crank sensor and main / fuel pump relays.

[RoyalW/BlauCheese]

found my cps/pulse-generator like this:

[RoyalW/BlauCheese]

getting a new one today. Curious to how much this will fix my issues...

[jeffnhiscars]

That looks fine to me lol

How do you even know what it is ?