No timing advance, I am stuck at 5 Degrees.

4g63mightymax · 09-05-2006, 08:26 PM

I am sorting out a few bugs on my 2nd 4G63 Mightymax build, and I have a problem that I am stuck on. I have a completely stock 1991 4G63 turbo engine with a 90 ECU (with the two wires swapped). I use MMCD v 1.8 on my palm to read my engine info and my timing is stuck at 5 degrees. No matter how I drive, or what I do, it is permanently at 5 degrees. I can even turn the CAS and have the palm still show 5 degrees timing. My timing light tool adjusts normally when turning the CAS. I have swapped ECU's and CAS's with absolutely no difference. My ignition timing ground connector is not grounded, and if I do ground it, the engine doesn't change rpm, sound, or anything.
I dont have my VSS wire hooked up and I dont have the coolant sensor that goes between the thermostat and the radiator cap hooked up either. Other than that, everything is wired up just like a 1991 eclipse.
Has anybody come across this before?

Steve the wiseman / computer guru, any ideas?

Thanks in advance!
-Jeremy

spyderturbo007 · 09-06-2006, 05:56 AM

Did you make sure that the logger was set on DSM and not in 3000GT mode?

4g63mightymax · 09-06-2006, 06:51 AM

I sure did, but I will definitely double check to make sure that I am not doing this

Have you actually seen this happen before with it on the 3000gt setting?
-Jeremy

spyderturbo007 · 09-06-2006, 07:37 AM

Not this particular problem, but there have been many reports of "weird, spooky stuff" happening when the logger is in 3000GT mode.

4g63mightymax · 09-06-2006, 06:20 PM

I definitely have my logger setup up right, and I even tried another one to see if mine was toast. Unfortunately for me, both loggers work and my timing is still stuck at 5 degrees. I did hook up the other coolant temp sensor and it made absolutely no difference at all.
I am baffled, does anybody have any new thoughts on this? I feel like I have tried everything.
Thanks
Jeremy

spyderturbo007 · 09-07-2006, 05:58 AM

So, just to clairify, the timing light is showing that everything is normal? You are just having a problem with the software receiving the correct timing value from the ECU?

4g63mightymax · 09-07-2006, 06:51 AM

If I set up the timing light, and turn the CAS, I can watch the timing change. Then if I go plug in my Logger, it says 5 degrees no matter where I set the CAS at. The real problem here is that the ECU is not doing anything with the timing. It is stuck at 5 degrees, and not advancing when I drive it. If you were to plug in your logger, it should show the timing bouncing around and you should be able to watch it advance then retard when you floor it. Mine doesn't. It is 5 degrees all the time. This makes my 4G63 Truck very very slow. I am guessing that the ECU is seeing something that it doesnt like and preventing timing advance. I have tried a different ECU, CAS, and logger and they all have the same results.
I wish I knew exactly what causes timing advance to work and which sensors are involved. I don't have a check engine light or any fault codes. I have the truck wired exactly like a 1991 eclipse should be, and this is the second 4G63 truck I have built. My first one ran great.
Any new ideas?
-Jeremy

spyderturbo007 · 09-07-2006, 09:10 AM

Quote:

Originally Posted by 4g63mightymax

Any new ideas?
-Jeremy

Sorry Jeremy, I don't have any other ideas. Hopefully one of the wisemen will stop by and offer some suggestions.

andymoraitis · 09-07-2006, 09:21 AM

Jeremy and Nathan,

I'm going to PM our resident ECU guru (steve) and see what he thinks. It may take a bit, but he always manages to figure things out.

FORMONTOYA · 09-07-2006, 09:44 AM

I'm not sure how the 1G works, but on a 2G to check the base timing you have to ground a timing circuit. If it's the same on a 1G...is that circuit ungrounded?

I know it sounds stupid.

4g63mightymax · 09-07-2006, 10:27 AM

Andy,
I greatly appreciate it, and as for the other post, the ignition timing adjustment connector is not grounded. I can follow it all the way back to the ecu and it is a single wire, not touching anything else. Whether it is grounded or not, the timing is stuck at 5 degrees. Grounding that terminal makes no difference at all in how the engine runs.
Keep the ideas coming!
Jeremy

4g63mightymax · 09-09-2006, 11:31 AM

For those of you following the 4G63 Truck timing saga, here is today's update. I had a few minutes this morning to mess with the truck, and realize that I had a wire hooked up wrong. It turns out that the black w/ yellow stripe #6 (i think) wire in the MPI relay was getting ignition power instead of power ONLY when the starter solenoid was working. This was causing me to feed power to the MPI relay all the time and telling the computer that the engine was constantly in the "start" position. The computer starts the engine at base timing, which is 5 degrees. Therefore my engine was stuck at 5 degrees all the time, no timing advance. So now I just have to reset my idle (because it is slightly higher than I like) and get some more gas in it, because I ran it out in my driveway.
Thank you for any and all help that I had along the way.
Case closed (for now)
-Jeremy

FORMONTOYA · 09-09-2006, 03:20 PM

A big

for finding the problem, and especially for sharing the solution as a reference to other people who might encounter a similar issue.