Stranded In Parking Lot

[Fumomike]

So as i am writing this on my iphone i am stranded at a bank of america parking lot. The temperature is like 87 degrees but i know when summer hits it will be absolute hell.

Anyways, the car is a 90 760 turbo, just as i was writing this the car decided to start.
It will usually not start when i am normal cranking but will start a little earlier when i push on the gas while cranking. It will catch a little and keep catching until it actually starts. Once it has started up the rpms will go up and down between 500 and 1000. Afrs will be lean too for some reason.

Car only does this when warm or hot.

Things i have replaced:
I have three radio suppression relays. At first i thought it was this and switched them when it was hot, it was not this. Also checked wiring from my other thread and it is a ok.
I have a brand new crank position sensor in there(2 weeks old)
New fuel pump relay

So i hear power stage amplifier might be it? I dont recall the car doing this with stock injectors...

[ZVOLV]

2 min is a spark check.

2 min is blast brake cleaner or starter fluid down its throat.

[ZVOLV]

Once spark is verified unplug the injectors and see if you can clear flood. Or pull plugs amd clear flood and start it on ether.

[Fumomike]

Originally Posted by ZVOLV

Once spark is verified unplug the injectors and see if you can clear flood. Or pull plugs amd clear flood and start it on ether.

What do you mean? Spray break cleaner on the power stage? So when hot and when it doesnt start check for spark, just remove one spark plug only to make it easy right? Power stage amplifier will do this?

Yeah during winter time car will run pretty well, now not so much.

[Owsley]

Engine Coolant Temperature Sensor. The one that tells the ECU what the engine temp is. That's what it sounds like to me. If it isn't bad, it soon will be. A $25 part. Get a real Bosch one, not aftermarket from the auto store. When these fail, they are intermittent and often show up during warm engine conditions. If the car is easy to start after it has cooled down for half an hour, then that's what it is.

[2manyturbos]

^^ I agree that it could be the ECT, however, saying that if it starts once it has cooled down points to the ECT is a huge stretch. Starting after cooling down would be much more likely a bad power stage or the sensor in the distributor. That said, the lean condition does point in the direction of the ECT. It could be way off scale telling the ECU to lean out to the point the engine won't even start. Easy to test if you own an ohmmeter. I would test it right at the ECU so you get the entire circuit resistance reading.

[ZVOLV]

Click my sig.

[Fumomike]

Ooo yeah. I'll do some tests tomorrow for spark after driving it for a while. Compression test done/checks out. all that is left is spark, and starter fluid. Then maybe air idk... Camshaft shims? If all checks out then im thinking i need to go get that ECT and powerstage.

Even at night time when it is cool. I had a hard time starting it when warm "temp gauge half wayish," had to mash the gas pedal while cranking to get it to catch. And catch is literally the word. I watch the tach and wait for the cranking and mashing on the gas to pop up the tach, thats when i know its finally catching. Hopefully its a easy fix. After looking at where the ECT is, it will be a huge pain to get to it. Do i need to remove the intake manifold? might as well do some cleaning if i have to do that.

And checked your sig. I'll give it a try and get back with ya'll.

[thismachine13]

Don't remove the AMM or any of that jazz to swap in the new ECT.

Changed the ECT on my '90 244 in about 15 minutes....tops. 19mm longish socket connected to a wobble joint to an 8" extension and a ratchet. Reached it from on top of the engine, through the intake manifold. A little teflon tape on the threads of the new one and fished it into the hole, then ratcheted it tight.

[philski o'flood]

your car is 27 years old, you should just replace everything

[Hotdoggin]

I usually pull the throttle body to change ECTs at work. Deep 19 socket, 8-10 inch wobble extension, flex head ratchet. They're easy to get to with the right tools.

[thismachine13]

I mean.....$20 at a Harbor Freight for the extension, wobble joint and a 19mm long socket. Sounds a lot easier than pulling the throttle body. YMMV.

Then again.....this is the TB forum.

[lummert]

You can swap out the ECT in 15 minutes. All you need is a 3/8 inch ratchet, 4 inch long extension, and a deep 19 mm socket. Unclip the connector, Place socket with extension onto the sensor, attach ratchet to the extension and loosen while watching out for your knuckles.

[Otto Mattik]

Did it easy with only a 19mm deep impact socket & 3/4" racket

[Fumomike]

Wow Power stage is ridiculously expensive. Not a part i can just randomly switch it. better test for spark first.

https://www.fcpeuro.com/products/vol...dule-3501921oe

[Harlard]

You can test the ECT by putting a multimeter on the pins at the ECU connector and measuring resistance. A borked MAF or ECT is the likely cause. Seeing as you already have rich mixture codes this would make sense. Have you tested the things I recommended via PM?

[Otto Mattik]

Parts Cannon ?

* I saw these "Martin's Auto Parts" power stages on epay for $19.02 (quality??)


http://www.ebay.com/itm/Ignition-Mod...tXsrKm&vxp=mtr

[Fumomike]

Originally Posted by Harlard

You can test the ECT by putting a multimeter on the pins at the ECU connector and measuring resistance. A borked MAF or ECT is the likely cause. Seeing as you already have rich mixture codes this would make sense. Have you tested the things I recommended via PM?

What things again? I'll check. I reset my codes, no rich mixture codes atm(one week since reset). However I am running rich at boost(550C). Just giving it time and fixing this hot start problem.

[cleanflametrap]

Originally Posted by thismachine13

Don't remove the AMM or any of that jazz to swap in the new ECT.

Changed the ECT on my '90 244 in about 15 minutes....tops. 19mm longish socket connected to a wobble joint to an 8" extension and a ratchet. Reached it from on top of the engine, through the intake manifold. A little teflon tape on the threads of the new one and fished it into the hole, then ratcheted it tight.

Do remove the AMM hose from the TB to open up access to the ECT sensor. Do look at the connector before changing the part; make sure it is clean where the contacts are. These sensors are rarely bad, so save your suspect one. Do not put teflon tape on the threads. Have the replacement handy so the coolant loss will be insignificant. The threads are straight, don't lose the copper crush washer, and the LH2.4 version depends on a ground through the head. Just another TB'ers two cents.

[ZVOLV]

Man the parts cannon!!!!

Throw shims at it!? Powah stage too!? Maybe it's the crank sensor or the compression!?

Slow down and learn how to test components.

Your car has been very modified. I wasn't surprised to see a thread like this.


Hard start with flooring it is likely flooding.

[ZVOLV]

Are you still in the parking lot?

If i had to guess i would say flooding from oversized injectors.

[Fumomike]

Originally Posted by ZVOLV

Are you still in the parking lot?

If i had to guess i would say flooding from oversized injectors.

Yeah thats what i was thinking flooding from oversized injectors, strage how it happens only when hot though.. I am not in the parking lot, after like 20 min it started and let me home.

[PromiseRing]

Symptoms are identical to mine when I had a bad fuel pressure regulator. It would hard start reallllly bad when warm.

[ZVOLV]

I recommend doing tests. Don't waste your money on parts darts.

For example, think it's the fpr? Get a gauge on there!

Think it's the powerstage? Sprak test! LED light will read the 5v square wave signal FROM the ezk. No scope required.

Think it's the crank sensor? Scope would probably be best, but even the LED test light will blink for you if it's working.

I recommend buying an LED test light.

[PromiseRing]

Originally Posted by ZVOLV

I recommend doing tests. Don't waste your money on parts darts.

+1 but you can smell the vacuum line on the FPR to give you an idea as to whether or not the diaphragm is leaking.