OK, guys...first post, and I need some help, please. I converted my 870 to a 165 a while back, and I'm having a few problems...hope you can help. Something is just not quite right here. I have back-probed the connectors, and all the voltages seem to be correct, according to the FSM. I ran new wires to the ALDL connector, because the old ones were in such bad shape....20 yr old wiring!! The car has taken to not starting, recently....I've checked everything: has spark (Nearly knocked me to the floor when I accidently grabbed the coil), has fuel (38#'s at the rail), new maf....but just cranks, and cranks, but won't ever catch....tries to, but won't. Timing is set to 10*, and is right on the money. Does this for a few days or weeks, and then wham! starts up??? don't know why?? I've tried to scan, but I CANNOT get it to connect at 8192, with any software. Tried Tunerpro RT, datamaster, turbolink, freescan....no sync. They all find the cable, and say it is ok. The TTS ALDL tester passes ALL the tests, both fast, and extended....I can however, connect @ 160 with WinALDL, or Tunerpro RT. Datamaster says it finds a GM 160 PCM (never been able to get a good answer on what that means, but I would guess it finds a 160 baud PCM)...Freescan says it get invalid header information...Turbolink just says it can't communicate....been chasing this for about 6 weeks, so I'm hoping I can get some help here on the Forum...BTW, I have an 85 vette, L98....
Checked the ignition module...it checks good, as does the coil.....ANY help would be most appreciated....

Cheers,
Michael

 

Get a noid light connected to any injector plug and see if you are triggering the injectors.

 

Sorry, i should have noted that above, but I felt the post was long enough...checked the injectors with a noid, all flashed...ohm'ed all injectors, and all were at or very near 16 ohms....new plugs, all properly gapped....

 

Although you mention you noided the injectors, did you disable VATS if applicable?

 

It sounds like VATS to me too.

It also sounds like you are using a 1987-1988 chip that will not do 8192 baud. Some will and some won't. Try a 1989 ($6E) chip for 8192 baud comms.

 

Not being the greatest on the MAF stuff but I'll throw my thoughts in.
If it were VATS the injectors would not pulse, so rules that out.
I'm thinking a intermittant TPS or CTS issue that may be under fueling at those times.
38# is a bit low and might help to bump it up if possible or add a bit in the crank table.
That is assuming the TPS and IAC are reset correctly.
Might want to try a shot of starting fluid to confirm that it needs more fuel to start. If that doesn't do it you could have too much and need more air.
Does moving the throttle help to get it started or are you just stuck when this happens?
Do you wait and then it starts?
Does this have the cold start injector in use? Could just need that little shot to help out.

 

No, vats is programmed out of the chip...tried starting fluid, but no go...the damn thing just cranks, and cranks, but no start...when it does this, it's like this for a couple of days, or weeks...then all of a sudden it will start! when it does start, it'll run pig rich, sputter and cough, but run. I'm using an ARAP bin, with the vats set to off, so i would hope it would connect to the laptop @ 8192...but I get nothing.....Thanx for the suggestions guys, guess I'll just keep pluggin' until I figure this one out...

 

Pull the plugs and clean/replace them. If starting fluid would not make it hit then you have too much fuel and probably fouled the plugs.
Open up the TB a little with the mechanical setting and reset the TPS.
Unplug the cold start infector if you have one and try again.
IIRC the cold start injector is not controlled by the ecm and is just fired with key on when temp is low. Not sure but that may be something to look at if you are fouling plugs.

 

Pulled the plugs...definately fuel fouled, and I've got the TB opened to the point where if it does start, the idel is up around 1800...I'm afraid to open it up any more...If I adjust the injector size in the Bin, do I need to go up or down in size to lean it out??

 

Right now don't worry about leaning it out. Barring any severe mechanical issue, it should at least run on ARAP. Just make sure the cold start injector is unplugged to avoid flooding the engine on startup, which it seems might be happening (the days/weeks between starts gives the fuel enough time to evaporate out of the cylinders).

When trying to connect via ALDL, do you have the 10k resistor between A & B? This is necessary.

 

Thanx Magnus....no CSV, I removed it...and yes I have a 10K resistor in place between A&B...every program I try "sees" the ECM, but won't connect at 8192....this is just driving me nuts!! Everything connects @ 160, nothing connects @ 8192....what am I doing wrong?!?!

Thanx to all for your input!!

 

What year bin are you using?

 

I'm using a $6E ARAP...I've always seen that as an 89 Corvette bin....

 

I should mention that last nite, it started up un the first crank....surprise! It would run, if I held the TB Blades open just a bit...I couldn't adjust the idle screw any more, since it is screwed all the way in....It died after a bit, and as I was trying to get it to crank again, I noticed what appeared to be little puffs of white smoke coming from around the injectors where they connect to the fuel rail, and where they go into the bungs....I assume I have some bad o-rings there....hopefully you'll tell me this is where my problem lies....gonna change the o-rings, as it doesn't seem to be a good idea to be running the engine with these bad......let me know if I'm on the right track!!??

 

$6E should connect at 8192 just fine. Must be a wiring or setup problem.

The TB screw is all the way in? Did you double check the engine timing with a timing light? Try unplugging the MAF and starting it?

 

Yep...tried all of those....timing is right on at 6*...when it starts, it starts with the first crank when I turn the key.....runs like crap when I unplug the MAF....no codes....gonna do the injector o-rings, and hope that clears up the starting problem...about the 8192 connect....I can see the serial output with a VOM connected to the "E" pin...seems to swing fine, just not very fast...I'm at a loss on the 8192 connect....every program says it "sees" the ecm...just wont connect...the datamaster ALDL test passes every test, both fast and extended, so I don't think I have a configuration or cable problem....just can't get the ecm to kick over to 8192.......

 

Try a different bin (like a production bin). ARAP and APYP were magazine bins and are aggressive. Is your car a manual or auto? I don't see that in any of your posts. 350 or 305? For manual, at least use APYP (ARAP is for autos). If you have a manual, I'd recommend ANZA, however (you can get it from my site).

 

Thanx! Magnus...I've got a 350 l98 with an auto 700R4....when car starts(ha!) it seems to run pretty good with the ARAP...thought I might substitute a less aggressive spark table, but otherwise, seems to be ok...but I wish I could figure out how to get the 8192 to connect so I could get some good datalogs...Winaldl logs seem to show things as being fairly good...just want to figure out the 8192 thing....

 

IIRC the 8192 baud data is on a different ALDL pin then the 160 baud data. Now, the two pins are connected together with one wire to the ECM. Depending upon which cable you use it may actually try to switch to the other pin, and if it isn't wired in then no data. Pins are E & M.

The 8192 requires a 2-transistor or bi-directional cable. Some cables for 160 baud are only uni-directional. Hope this helps.

RBob.

 

Yep, the cable is a bi-directional cable, MAX232...got serial data to pin "E" and Pin "M"...both from the same ECM pin, I believe it is "A8" or "A9"...both pins are connected to the cable...