for those of you that have forgotten, and the rest that didn't know (or care I suppose), back in April the car went into the garage so that I could swap the stock 85 ECM out for a 165 ECM. I also swapped in a wiring harness from an 87 IROC, a distributer with a divorced coil, accel super ram base, SLP runners, new fuel rails and a Holley throttle body. I figured 2 weeks because I was taking my time, cleaning and painting everything ,etc.

Well anyway... last night I finally fired the damned car 3 months behind schedule. It won't idle, but it runs. I think I installed the distributer off a gear, making it too far retarded. I had to turn it nearly 30 or 40* counter-clockwise to get the idle to come up higher and higher, but I still couldn't get it up far enough for it to idle on its own. I couldn't turn the distributer any farther. So... tonight I'll move it 1 gear over and keep turning. Assuming that works and I don't have other problems, then I'll just have to come up with a PROM editing program that installs, runs and also allows me to save my edits (None of my current copies seem willing to do all 3) so that I can begin to fine tune things.

But... as bad as it ran, it didn't throw any codes, so it seems promising that everything is wired properly and that the 165 ECM likes the 85 MAF. It also didn't have the usual 2 black puke stains under the tail pipes that it always used to with the old ECM.

 

Right on


My 870 > 165 swap took me about 30-40 minutes, than I fired it off and drove it to the store, then home, its been running the 165 perfectly ever since. Now the '730 Is going in when my memcal shows up

 

How do you set your timing?

 

Well, after I turned it 1 tooth, I kept starting the car while my father screwed with the distributer until it would run well. I'm having idle problems so for now I had to just adjust the idle screw on the TB to get it to idle. Then I shut the car off, unplugged the little plug over the heater box, started the car, set the base timing to 5 or 6* (I want it conservative for now), shut the car off and plugged the little plug back in.

Now I just need to figure out how to get it to idle right.

But so far I'm pretty happy. It runs, it doesn't leak fuel or coolant (at least not yet ) and it doesn't seem to be running pig-rich like it used to. The tail pipes used to spew so much black that it would stain the floor. So far I've got absolutely no black marks on the floor... just a whole lot of water from the condensation that's been building in the pipes thanks to my very moist garage.

 

How can you get the dist 1 tooth off? The oil pump drive will only allow the distributor to go in all the way, 2 ways. Either dead on or 180 out. Otherwise it shouldn't (Emphasis on the shouldn't. these cars don't seem to follow physics ) go all the way down and rest on the intake if you only go one tooth.

 

Turn the oil pump drive. I installed a new (well, new to me) distributer, not the old one, so I couldn't really just drop it back in place without difficulty. I cranked the motor to TDC, then used a screwdriver to turn the drive to where I thought I needed it, but I was off a tooth. Basically it's all a wash, but I wanted the distributer oriented a specific way so that it's easier to unplug the wires at the base of the distributer.

But anyway... it seems that my idle problem was due to a faulty IAC. My scan tool showed an IAC count of 160 and it never moved. I unplugged the IAC and the idle didn't even change. The IAC coils tested 50 ohms, but I'm still guessing that the motor seized and still had intact coils. I bought a new IAC. I just installed it but I didn't start the car and set the minimum idle yet. I'll post an update shortly with my results.

 

New IAC didn't change anything. I put the ECM into diagnostic mode and verified that there's voltage on all 4 pins of the connector that plugs into the IAC. That rules out wiring and should rule out ECM problems, but my IAC still isn't working.

 

So When you Say Won't Idle, You mean it Stumbles and dies ?

Vac Leaks ?

 

It would stumble and die. I don't believe that I've got any vacuum leaks. When I brought the throttle blades out far enough, it idles at 650 very well. With a vacuum leak you're likely to get surging up and down that causes an unstable idle. This just stalls like it doesn't have enough air. Once I give it the air, it idles nicely.

 

Put a scanner on it and see what the IAC counts are at idle. If the iac is maxed out (160 IIRC) trying to get it to idle, then you just need to give it some more minimum air. I like to set mine so that at a warm idle the IAC counts are moderately low, like 20 -30 ish.

 

Yeah, I'm way past that. My IAC counts are pegged at 160 and the ONLY air that the motor gets is coming from the throttle blades being open. I haven't had time to pull the lower half of the throttle body apart to check for blockage, but it's either the IAC passages that are totally blocked or the IAC is staying totally closed. Since it's a brand new Holley TB and I cleaned the hell out of the lower housing before I installed it, I can't imagine it's blocked.