Base timing strangeness

[Shadow]

Having trouble getting base timing (distributer in right position) on a 2.2 in the shop. First time in over 15 years that one of these mtrs with proper tiiming marks all lined up 100% And oil pump gear clocked correctly has the distributer sitting slightly to the left of a flat plain to the mtr instead of to the right.

Other thing to note is the DRB2 shows 18 deg timing at idle while I have it on the timing gun at 12. The TPS was reading a little high (3%) at idle, so I solved that and am going to check it again after lunch.

Can the pick-up in the distributer throw your timing out that much? anything else?

[shadow88]

I thought the drb2 included the advance, or "total timing" that's why the timing light and drb2 display don't agree.

[Shadow]

Well, something is deff adding timing. I set the base to 12 deg on the window and DRB now reads 27-28 deg at idle and the idle won't come down umder 13-1400rpm. Rev'd right up when I set the base timing and won't come down. AIS hits it's target of 32 (why is it targeting that high?) but RPM is targeting 940 and won't come down.

Now, if I back off the distributor till the DRB reads 18 deg or less (1-4 deg base timing in the window) then idle targets fine and everything is peachy

So, any suggestions? Pick-up giving a false sinc signal?

[turbovanman²]

As long as you can get the proper base 12 deg timing with the coolant sensor unplugged, cam timing ok, then let it be,

[Pat]

Check the speed sensor. I had a car that the sensor read a constant 5-7 mph. This kept the idle high, which meant I couldn't get it timed right.

[Force Fed Mopar]

You do have the coolant sensor unplugged right? You can't really set the timing using the DRB, have to use the light.

[BadAssPerformance]

Are the distributor shutter plates extremely loose at the heat-staked plastic parts? or the I-shaft/o-pump gears really worn?

Check the speed sensor. I had a car that the sensor read a constant 5-7 mph. This kept the idle high, which meant I couldn't get it timed right.

+1 to this, had this happen as well. IIR code 15 maybe?

I had another one that seemed to be the same issue and also threw the same code, but was actually a bad orange wire in the fusible link loom.

[RoadWarrior222]

Check the speed sensor. I had a car that the sensor read a constant 5-7 mph. This kept the idle high, which meant I couldn't get it timed right.

Shadetree license fail... shoulda rolled it down a hill backwards at 5-7mph while you timed it

[BadAssPerformance]

Shadetree license fail... shoulda rolled it down a hill backwards at 5-7mph while you timed it

Pat's good, how do you know he didn't do that! LOL

[Pat]

Are the distributor shutter plates extremely loose at the heat-staked plastic parts? or the I-shaft/o-pump gears really worn?



+1 to this, had this happen as well. IIR code 15 maybe?

I had another one that seemed to be the same issue and also threw the same code, but was actually a bad orange wire in the fusible link loom.

Mine never triggered a code...I just happened to see on the scanner while trying to figure out what the issue was that the car was supposedly rolling at 5 mph.

Shadetree license fail... shoulda rolled it down a hill backwards at 5-7mph while you timed it

LOL! Bigtime fail...didn't thank of that one!

Pat's good, how do you know he didn't do that! LOL

Try explaining that one to the wife: "Honey, it's fine. Just drive backwards down the block, between 5 and 7 mph, while I run next to the car to set the timing. If you hear a scream or lose sight of me, stop...you just ran me over."

[RoadWarrior222]

I'm not sure if it actually works though, the electronics count the pulses, not which way round the wheel is spinning...

[Shadow]

As long as you can get the proper base 12 deg timing with the coolant sensor unplugged, cam timing ok, then let it be,

That's a big Negative! Something is wrong and I won't be able to put it out of mind until I find it............

---------- Post added at 06:50 PM ---------- Previous post was at 06:49 PM ----------

Check the speed sensor. I had a car that the sensor read a constant 5-7 mph. This kept the idle high, which meant I couldn't get it timed right.

I had thought about this, but no codes and haven't looked at it on the scanner yet. Good call though, I believe I had one with this same problem some years ago.

[Shadow]

Always unplug coolant sensor for base timing, oil pump is new, mtr is fresh with good I shaft gears. Distributor plate is rock solid.

Went for a cruise to town after retarding timing enough to get it to hit idle target of 912rpm. Got to town, idle sat at 1500rpm, then fought to drop down to around 1300. As I drove stop and go through town it settled in at 1500. Every time I slowed down you could hear it want to come down and then just as I stopped it would raise up to 1500 again.

Shut it off and went shopping. Started it and it started lazy and took a bit to step up (500rpm) then rose to 2000rpm. Stayed there for 3-4 lights on way back home. Finally at the second last set of lights I got tired of it and out of desperation I gave the throttle a good Stab, like in the old days when you would stab the throttle to knock it off high idle.

Surprisingly it dropped right down to 912 rpm and started behaving. Hit the last set of lights and same thing, 912rpm, everything seemed fairly normal (except the dizzy being in the wrong location) even the timing on the DRB was down at 18 instead of 26-27.

Got back to the shop and let it idle. Was going to change out the AIS before it dropped on the way be as I couldn't figure how it seemed stuck at 32 target. Anyway, for the first time the AIS was at 26 targeting 26. Idle was hitting target. Then after about 5min it jumped to 32 target again and idle went up to 12-1300rpm.

Gonna think about it some more, but it almost seemed like the TB was sticking open a bit and when I stabbed it, it shut and the AIS had to open a little to compensate?

I had pulled the AIS out earlier and cycled the ignition to get it to step out further than 32, just to make sure it could. Bolted it back in and fired it up, 500rpm, 47 step and then quickly changed back to target 32 / 32 step and 1300rpm.

I'll check the distance sensor first thing tomorrow!

[RoadWarrior222]

I had similar behaviour when I had a crack in a vacuum elbow... it was kind of erratic, because being through sorta thickish soft rubber, I think it managed to suck itself mostly closed, then it would get joggled by a bump or something and be wide open... then joggle to a position it could seal again.

[Shadow]

Fired it up this morning, looked at the distance/ speed sensor, was normal at 0. Looked at the TPS, was reading 12%, Damn, so the TPS is either temp sensative or just plain Bunk. I swap out the TPS and everything gets better, AIS is acting normal, target RPMs are dead on ect.

So, all seems good, but we're Not done yet, not till the distributor problem is resolved.

I look at the DRB timing and it's reading 18 deg. I put my timing light back on the mtr and I can't see the timing mark, Beautiful! I crank the dizzy all the way back to were it Should be and there's my 12 deg base timing! Yeha! Look at the DRB, still reading the same 18 deg timing.

So, thanks for all the help and suggestions guys! Really glad this was as simple as it Should have been! Still, never knew a bad TPS could mess things up this bad, one to put to memory for sure!

[Vigo]

Nice, i will keep this in mind if i ever run into that!

[Shadow]

Yeh, I thought I'd post it for help + in 15 years of messing with these mtrs I had Never seen one mechanically correct (ie. proper timing on mark, I-shaft clocked right ect) that did Not put the dizzy in pretty well the Exact same location at 12 deg base timing. Matter of fact, it's so exact that I set the base timing by clocking the dizzy when I'm assembling and am usually dead on or 1-2 deg out at worst. That's why this one had me going Hmmmmmm........

Never would have guess the TPS could do all of that though!

[trannybuster]

Ooo...good to know, Im having the exact same issue with timing, it shows 24 with scanner but its spot on with timing light, I know its a issue somewhere else because I actually moved the dist ahead becasue the light said so BUT it was fine last season, now Im getting detonation everywhere. Thanks for postiong up the final fix!!

[Keito]

I had high idle issues when I first bought my GLHT, if I wiggled the LM connectors it would drop the idle down.
I pulled the LM and water had corroded the blue and red LM connectors.
I bought a new wiring harness from the dealer, I think the parts guy said it was the last one he could find, paid $185 if
I remember correctly. Long time ago.