[Green Machine]

Looking for any guidance from the wise ones on my many " gremlins"...
I'll try and keep the story short but keep the relevant parts of it.
I purchased a turbo kit from an unnamed vendor, got zero customer service and after 4 attempts was stuck with a crappy tune. Took the car up to Hahn's in Daytona to have him look at it.
After sticking the stock tune back in he was able to get it running way better but it has now started a series of gremlins and I am suspecting the ECM but not sure where to start troubleshooting. Here's a list of the issues as they appeared and if or what I've tried.

Speedometer not working now, worked on the way up, never had an issue and Bill said its not worked since he got it?
Checked fuses and connections at the tranny, not ready to replace the sensor yet until I've done a little more poking around.

Throwing code 0606, ecm,pcm communication, info center shows reduced engine power?? I can clear the code and code may come back instantly or will stay off for random amount of time..
Tried putting stock tune back on and it still throws the code and no Speedometer.

Very hard starting since swapping the fuel injectors and adding the turbo. before the newest tune it would crank over and never "catch" until the third or fourth try and would have to hold the pedal down to the floor. It also smelled of raw fuel from the exhaust once it fired up..
It still starts hard with Hahn's tune in it but the "raw" fuel smell is now minimal and doesnt smell like its dumping fuel at start..

Last issue, yesterday i was driving around with a quarter tank of gas and as I came to a light the gas gauge dropped to empty, it went back up as I pulled away which I have never seen before. I watched it slowly drop from quarter tank down to empty and back up 3 times before I pulled in to a gas station and put 10 gallons in it. It stayed at 3/4 tank the rest of the drive home..
The last gremlin I'm not sure wasn't some fluck, but is what made me think ECM may be going. Its been re flashed at least a half dozen times while trying to put a remote tune in it and at least 4 or 5 times by Hahn..

I am supposed to bring the car back up to Bill and he suggested checking all the grounds and connections and then trying a known good ECM in it before replacing it. I would like to try and do as much troubleshooting as possible before I do so I can keep him concentrated on the tune and not troubleshooting gremlins.

I looked it up and an ECM isn't much more than the speedometer sensor and although money is irrelevant with these cars I didn't want to just buy a sensor and still need the ECM anyway without troubleshooting first. My thought was to just have a new ECM ready to swap when I bring it back. It was a slow process to get the tune from Bill so trying to save myself and him some aggravation.
Any thoughts or experiences are gratefully sought, I would be way further behind on this project without the input and help I've gotten from everyone on this forum 👍

I have an issue with the dipstick also, it appears to keep popping up since the turbo install but I may need to just start a different thread on that one for now. Bigger issues first...

 

[Green Machine]

Oh yeah, I forgot that when you hit the key fob to lock it the horn puts out a weak honk like the battery is low but checked everything obvious there as well and no culprit besides maybe back to ECM issues?

 

[sahein]

Check your battery voltage with the headlights on with engine not running. Check voltage between positive terminal and frame ground. Speedometer issue could be a problem with the vss.

 

[Green Machine]

It's been raining here all morning, finally clearing up so plan on pulling it out checking the voltage and need to jack it up and drop the cover to check the speed sensor. Any idea if it can be checked? I'm assuming either voltage or resistance is how it works but don't now if it can be checked without just swapping it. The Delco sensor is about $100 though , a little much to just guess yet.

 

[jimreally]

It's been raining here all morning, finally clearing up so plan on pulling it out checking the voltage and need to jack it up and drop the cover to check the speed sensor. Any idea if it can be checked? I'm assuming either voltage or resistance is how it works but don't now if it can be checked without just swapping it. The Delco sensor is about $100 though , a little much to just guess yet.

After my Base 2.4 started giving me fits, I went through a bunch of troubleshooting, checking/cleaning all the grounds, various connectors, fuses, relays, changing the ignition switch, ect., I finally replaced the ECM and it seems to have fixed all of my issues. I purchased my ECM via ebay from a vendor called spareecm for $109. For my symptoms you can check out this thread: Sky runs rough and/or Won't Crank unless i...

 

[Green Machine]

After my Base 2.4 started giving me fits, I went through a bunch of troubleshooting, checking/cleaning all the grounds, various connectors, fuses, relays, changing the ignition switch, ect., I finally replaced the ECM and it seems to have fixed all of my issues. I purchased my ECM via ebay from a vendor called spareecm for $109. For my symptoms you can check out this thread: Sky runs rough and/or Won't Crank unless i...

Awesome, thanks. New one is worth it in time alone trying to troubleshoot. Checking the obvious for now anyway...

 

[Green Machine]

So my voltage at the battery is 12.7 , with lights on 12.24... with key on and lights 12.12
With it running I'm at 14.15 and 14.02 with lights on. Seems within normal parameters. Going under to check speed sensor next..

 

[sahein]

So my voltage at the battery is 12.7 , with lights on 12.24... with key on and lights 12.12
With it running I'm at 14.15 and 14.02 with lights on. Seems within normal parameters. Going under to check speed sensor next..

Did you check the voltage between the positive terminal and the car frame?

 

[Robotech]

It could most certainly be the ECM but you definitely want too check grounds like Sahein states. I had my ECM go bad after installing a turbo on my 2.4 but it was having a couple issues just before the turbo went on. Flashing them can cause issues but those are generally all or nothing affairs where the ECM bricks itself and the car won't do anything. Check grounds first before ordering more parts but if that is good, then it may be your ECM or harness. Who did the turbo install?

 

[Green Machine]

I've got good/consistent voltage (12.4) from the positive post to the frame, the block, even the pcm itself shows good ground... although obviously I'm checking the basics, with the weird behavior on multiple things the ecm is my suspect but not enough evidence yet..
I've got a sensor ordered and a ecm off ebay supposedly flashed to my vin. I plan on swapping out the sensor this weekend to see if it fixes the speedometer but will let Mr. Hahn swap out the module.
He put the tune in it and has my factory tune as well.
I saved the tunes the un-named vendor put on it as well just in case I ran into issues..

 

[Green Machine]

It could most certainly be the ECM but you definitely want too check grounds like Sahein states. I had my ECM go bad after installing a turbo on my 2.4 but it was having a couple issues just before the turbo went on. Flashing them can cause issues but those are generally all or nothing affairs where the ECM bricks itself and the car won't do anything. Check grounds first before ordering more parts but if that is good, then it may be your ECM or harness. Who did the turbo install?

I did the turbo install myself, drilling the block for the oil return was probably the scariest part but learned a lot about turbo's real quick!

 

[rjgramps]

moms car,

I have to ask this question. Have you closely inspected every connection at the ECM? Just a small amount of what I describe as "white chalk" on any terminal, will increase resistance and throw something out of whack.

Remove the ECM and inspect the terminals under magnification. Also inspect the connectors from the wire harness. Clean up anything suspicious. All terminals should look the same. Any terminals that look caulk-white different (or worse) may be the reason for your troubles. If so, also inspect the rubber connector seals. Maybe one is lightly deformed, allowing moisture to get inside. If you find that suspect, remove the seal, clean it up, maybe even boil it to form it back to it's original shape, dry and carefully reinsert it.

I had a Fiero-GT with a bank of 3 cylinders that would shut down at random. A little crusty chalk in an in-line connector was the culprit.

 

[Green Machine]

I haven't got that far yet. Basics so far but when I get the speedometer sensor I'll try and give everything a thorough check when I swap that. The ecm was a little over $100 so it seemed to make sense to have a known "good one" when I bring it back to Hahn's for the final tune.
This all started when he put the factory tune back in and started his tune. I had no issues with codes or the speedometer or the horn when locking before I brought it up there. It just seems like the culprit and along with checking everything obvious it would be my next step anyway. Fortunately it wasn't that expensive.
I'm listening and appreciate the input for sure 👍

 

[vrvillani60]

I haven't got that far yet. Basics so far but when I get the speedometer sensor I'll try and give everything a thorough check when I swap that. The ecm was a little over $100 so it seemed to make sense to have a known "good one" when I bring it back to Hahn's for the final tune.
This all started when he put the factory tune back in and started his tune. I had no issues with codes or the speedometer or the horn when locking before I brought it up there. It just seems like the culprit and along with checking everything obvious it would be my next step anyway. Fortunately it wasn't that expensive.
I'm listening and appreciate the input for sure 👍

You might want to check the ground on the forward right side of the cylinder head make sure both ground leads are clean and secure....

 

[Green Machine]

Both are, they got cleaned and had to move the angle of them to clear the turbo coolant line during that install . I've got good, consistant current off the positive terminal to them, off the frame anywhere I check and at the ECM as well.
Yesterday I checked every connection I could find, pulled every fuse and even cleaned the battery posts, again... I still get the code 0606 and its random, I can clear it and it may come on before I get out of the drive and otherwise it may stay off for an entire drive.. the weak horn ended up being just the horn. Laid on it for a minute and it "cleared it out"?? Not sure what that was about but I still have no speedo.
I have no data coming from my scanner for mph either so not sure if ECM trouble causing it.
I bought a speed sensor and spent half day pulling covers underneath to only find one plug with a lot of wires going into the tranny. I've searched the forum and could only find one thread that said it was inside the pan and then ends abruptly...
I'm going to search the solstice forum this morning to see if I can find any more info on it as my usual web search has turned up everything but where it is on the automatic. If its in the pan I may wait to swap the ECM before dropping it and see if thats the issue