85 245 lh2.2 Crank No Start, Int. Hard Cold Start

[Parc]

SOLVED: see 4th post


Overview:
-Brain Hurting
-Fuel Yes
-Spark Yes
-I have Timing Questions
-I have Vacuum Questions




Timing
This is where my distributor ends up when at TDC with cam pulley/crank sprocket notches lining up and the crank pulley notch at 0 on the cover. Should the rotor be centered on the tiny notch next to the hall sensor? Timing light on #1 during cranking indicates ~12degrees. I'm very confused but think maybe the timing has fallen off by ~5 degrees mysteriously since I last set it. The belts got a tightening recently, if too tight, could this have messed with the harmonic balancer? I had the cam out to do hushers and shims recently, and failed to line up the intermediate gear, ended up pulling the diz and rotating it on the teeth, is this a no-no?

I got it running yesterday by resetting the timing...and burning off the plugs...but it's back to no start today
During the running, when it's warm I can shut it off and restart. It has had a hard cold start for the last 2 months until this no start issue. The hard cold start is very rough 2 or 3 cyl firing for 20 seconds then it would run ok but with a hunting idle. Vacuum is steady at 10in, from what I've read indicates a possible timing or vacuum issue, maybe I have both (but wait there's more below). While engine running yesterday, I was searching for a vacuum leak (using propane) couldn't find any until I decided to pump the brakes and suddenly the RPM shot up. This was repeatable, but a problem I didn't have before or maybe I just missed it. The brake vac check valve is new. I didn't hear the hissing that others have heard from a blown booster (could it be so bad you wouldn't hear that?), strangely the brakes seem to operate normally as far as I can tell not driving it, but may have to hook up vac to do the proper test, or just go ahead and replace it. Clearly the brake booster is introducing air into the manifold, no? Is there anything else pumping the brakes could be activating?

I also have another thread open where I found that the tank pump doesn't run when cranking, which has been addressed by others on that thread, but requires more investigation.

To add insult to injury, I snapped a hood hinge last week. It was wonderfully simple to diagnose

Growing weary eyed
Any input much appreciated
Tack själv!

 

[bobxyz]

Timing light on #1 during cranking indicates ~12degrees. ... I had the cam out to do hushers and shims recently, and failed to line up the intermediate gear, ended up pulling the diz and rotating it on the teeth, is this a no-no?

I think you're OK with a rotated LH2.2 disti drive gear as long as the idle timing is correct - spec of: 12deg +/- 2deg at idle (750rpm) and vacuum line disconnected from Chrysler box. I don't know how this translates exactly to cranking timing, but ~12degrees seems reasonable.

You've mentioned wet plugs - maybe you have a leaking injector causing problems until the cyl. dries out? If you are very careful, and have 1 or 2 fire extinguishers handy, you can pull the injector rail with the injectors still attached, put a plastic bag around each of them. Then, with key off, jumper the fuel pumps for a couple minutes to pressurize the system and circulate gas. There should be no leakage. You can pull the cold start injector too (but it needs to be re-sealed when re-installed).

 

[Parc]

Thanks very much bobxyz, i haven’t done that test before. I figured the soaked plugs were due to excessive cranking. unplugging the injectors and cranking seems to work in burning off the excess, however the problem does come back when I continue to have no starts. I failed to mention I had changed the injectors from apparently original black tops to newer used yellow tops, which did not make any noticeable change to startup conditions, but did seem to improve running conditions slightly. I had also swapped a used pressure regulator, despite neither showing signs of failure. It is time however to get myself a fuel pressure gauge. And there is still more investigation needed at the tank pump as it still does not run during cranking (but does during running).

I will report back when I get time to check for leakage, I think it’s warranted. fuel pressure too, and reinvestigate red/yl wires to fuse #4

Circling back, the idle increases +100rpm with the upstroke of the brake pedal after each pump. If I understand the booster correctly, i think this aligns with 1. a bad seal around the apparently functioning check valve 2. a blown clever valve internal to the booster 3. a blown bladder internal to the booster

Will go over the booster again and recheck vacuum if I get it going

Any insight very much welcome

 

[Parc]

SOLVED

Crank No start caused by fault in Ignition Control Module (Chrysler 1346107). Not sure whether it's the vacuum bladder/sensor or something else within it. Installed a used one from ebay that looks like hell but works. Before, I was only able to start the car by manually rotating the distributor counterclockwise (retarding?) working off the premise that if there's fuel and spark than it must be air or timing.
Rough or erratic Idle caused by cheap Coolant Temp Sensor (AMR, sold by IPD). This was the big headache in more ways than one as I presumed (because it was new) that it was good and because it was one of the first things I changed without properly checking the old one, it sent me chasing red herrings for days. A simple ohm reading across the poles read 20,000 Ohms (It should have been ~2,000). This sent a signal that it was -30 celcius when it was +30 ... So I reinstalled the Bosch sensor and bingo.

More lessons learned and it lives another day!