well, that's what datamaster is telling me I've got? Might have the opti on wrong, might run out to the garage and check, just trying to get the engine running after sitting for 3 years and going through a swap into a gmc jimmy.

it will barely run w/ the throttle wide open, have a datalog of it, won't go above 1200 rpm. Not really looking for wide open speculation just wondering if anyone has seen anything like this.

have had a couple of intake bellow fires, was a 96 fleetwood motor, previous owner swapped out to aluminum heads, was meticulous in his work, pulled driver's side valve cover and rockers are tight (stock valvetrain).

Converting it over to OBD1, still have the OBD2 pcm, but have to wire up the vats circuit i made to try it. just plugged it in and got about 5 seconds of the same behavior. more of a novelty than anything else.

 

You stated that the "rockers were tight"; rockers are going to vary from tight to loose depending on what valves are opened/closed. Were all the rockers tight on the side you opened? If yes, I'd reset the lash on the entire valve train.

 

I meant it as in they were lashed correctly as far as I could tell, closed valve rockers would wiggle just a hair when tried.

Just pulled the opti, it was installed correctly, so I though possibly I reassembled it wrong (lightly cleaned opti pickup and disc w/ rubbing alcohol, knocked crust off rotor and posts on cap), and there is no way to assemble it wrong, it's all keyed. debating on picking up an opti from napa..

When I did shoebox's troubleshooting guide before I pulled it apart I was getting fluctuating voltages when checking @ the ecm, didn't know if my meter was fast enough to keep up w/ the cranking motor or whether it's bad. It'll run w/ starting fluid, can't tell if it's hitting on all 8 then or not.

 

If it's running on starting fluid, sounds like you're getting correct timing. Have you checked your fuel pressure?

 

You've got a data transfer glitch.... you aren't ever going to see 255deg advance on DataMaster. And it wouldn't matter if your Opti was installed totally incorrectly. All that DataMaster is showing you is what value the PCM picked off the spark timing table, based on the RPM and MAP - and I doubt someone entered "255" in the table when they programmed it. The PCM has no way of knowing if the Opti is installed incorrectly.

I've seen some ridculous numbers come out of DataMaster..... "255" is always suspect, because its the upper limit of an 8-bit binary field.

 

Thanks for the reply Fred, I was thinking along the same lines, have the stock program in the pcm. I was trying to figure out how the opti could have been offset to give me that kind of timing before I pulled it off. Going to dig further into it later on, sick right now and the garage is pretty humid from all the rain so i'm just being a wuss.

OBE, fuel pressure is 43 psi key on, engine off, sits at about 40 w/ the engine...running. have to keep it wot to keep it running, won't rev past 1200 rpm, map is sitting around 89 kpa, injectors are cycling, etc etc.

I might pull the fuel rail and attempt to run it to see if i get fuel to all the injectors and also to make a bigger mess than I already have. I might bring the opti in to work, power it off a bench power supply and borrow a oscilloscope to test to see if I'm getting both signals and reading it all the way around. I haven't tested the opti since the cleaning, but before w/ the multimeter test it was fluctuating from 2-4v ac, supposedly correct, but readings were erratic, and was getting pretty much the same cranking results as I am now, but the fuel pressure was off pretty bad, just now got the parts to fix my pressure gauge, waited a week, about killed me.

Have brand new MSD 8.5mm wires, new ngk tr55s gapped to .050", battery charger on small rice burner (free) battery, cleaned the posts and rotor (crusty), checked continuity and power to pcm / sensors, good ground, +12v to all injectors, brand new MSD blaster coil, brand new MSD fuel pump w/ brand new filters front and rear, 5 gallons of 93 in the tank, brand new TPS, it was bad to start with, power to opti and ignition control module, 3" impala MAF (showing activity w/ datamaster), brand new 1LE elbow, disconnected EGR, open stock manifolds. That's about all I can think of that would be relevent to this discussion. I have the .uni file if anyone wants to laugh at it and I appreciate you all hanging with me to help out.

Jeff

 

You may be using the wrong program. There is a program made OBD1 for 94-95 LT1s and OBD1 for 92-93 LT1s. The one you need is Datamaster EE 3.4.1.

 

Coolant temp sensor in the water pump. I chased a non running car for I can't remmeber how long until I changed this and it straightened right up. It was dumping fuel like crazy and wouldn't run on anything low RPM at all.

-Shannon

 

Thanks guys, I am using the right datamaster version, and I'm not really getting any fuel at all to be honest, can't really smell burnt fumes or raw gas, i can definitely smell the hell out of the ether when it shoots out the other end. Don't get me wrong, I can smell exhaust fumes when it's barely running, but it's not eye watering or nose burning, it's just there.

I did have the wp sensor hooked up previous to pulling the opti and getting the fuel right, will try plugging that in to see what happens when I get back out there.

The spark advance hits 11-13 degrees when first cranking, then when the engine catches it rolls on up to 253-255.

One other thing I forgot to mention is I don't have the knock sensor installed right now, it's got an OBD2 sensor in there and I haven't had a chance to get an OBD1, I would just do the parallel + 2.2k ohm resistor to ground for the OBD1 conversion, but I only have 1 sensor, the other sensor was damaged when the engine was removed. I've thought about figuring what resistor value I would need to get the 100k to read like a obd1, but would rather spend $20 and not worry about messing up the circuit.

Thanks again for the replies, all brain storming welcome, I am ready to see what a 300 hp all wheel drive launch feels like.

 

there's something about a vehicle sitting for a while, then going from a 2.8 carbed v6 to 43 psi of V8 happiness.

Installed new knock sensor, plugged in temp sensor, ran pcmcomm to make sure everything was reading the same as datamaster, then fired up datamaster, kicked the key on and datalogged, toof toof toof, nothing. well, air is there, spark is there, lets check the fuel.

I primed the system then pulled power to the fuel pump, then cranked the motor while watching the pressure, i could actually watch where it was sssslllloowwwlllyyy being relieved by the injectors, it should have dumped pretty quick if everything was working. Pulled the fuel rail, some injectors wet, some dry, so I ran a jumper to the fuel pump, primed the system, then jumpered 12 volts across all the injectors, only 2 of the 8 squirted fuel. reckon that's the reason why the motor was only running 25%. pulled the injectors, and man, the tops were PACKED!!!!!! Just got finished flushing them out w/ carb cleaner, letting the tops soak a little then going to blast them again. would fire the truck, but wife's on the other side of the wall fast asleep.

Hopefully will get it back together tomorrow night and will update w/ pics!!

I hope this is it and want to thank everyone that submitted.

Jeff

 

Thats cool. I'm glad things are starting to get figured out

I was going to say i've got a few OBD1 knock sensors laying around if you want one. I've also got some unknown LB/hr fuel injectors too if you wanna try those.

-Shannon

 

Thank you for the offer Shannon, I do appreciate it.

Got it fired up yesterday, ran rough as hell but started mellowing out. Also found the reason for the 255 spark advance..

The engine is a 96 caddy, block, manifolds, intake, and maf, the heads are 97 camaro, I THINK the pcm is out of a 94 caprice.

The tune was a little off to say the least. W/ the stock tune it would barely run, 255 advance, was getting ESC error w/ new knock sensor too!

So I got to thinking, pulled up a stock z28 tune, dumped a 9C1 maf calibration table in there, and wha la. She's running, a bit rich at idle, but its running, and man does it sound mean!! 10:1 w/ open headers, neighbors love me.

Here's some pics of the carnage, polished the fuel rails while I had everything apart.

http://216.77.188.54/coDataImages/p/...6Pb300013r.jpg

http://216.77.188.54/coDataImages/p/...7Pb300031r.jpg

http://216.77.188.54/coDataImages/p/...8Pb300036r.jpg

http://216.77.188.54/coDataImages/p/...0Pb300044r.jpg

http://216.77.188.54/coDataImages/p/...2Pc010002r.jpg

 

Holy cow those are dirty !!!

Glad ya got it figured out ! Your rich problem will probably go away when you get some exhaust on there if the O2 sensors are close to the end of the exhaust right now.

-Shannon