Idle problem cont. May have found solution...
Thread Starter
Melting Slicks
Joined: Jan 2008
Posts: 2,065
Likes: 1
From: Jasper Texas
A toyota, not a bad idea, at least I'll get good gas mileage. 
On a serious note, the computer and all of its functions are exactly what have made this tough to diagnose. Realizing this, and knowing I'm not exactly skilled with cars (especially fuel injected), I'm just taking it to my mechanic. He's worked many miracles for me before, and I trust him way more than myself. I don't want to screw somthing up and ruin the car, I've got way too much money sunk into it to do that.
On a serious note, the computer and all of its functions are exactly what have made this tough to diagnose. Realizing this, and knowing I'm not exactly skilled with cars (especially fuel injected), I'm just taking it to my mechanic. He's worked many miracles for me before, and I trust him way more than myself. I don't want to screw somthing up and ruin the car, I've got way too much money sunk into it to do that.
Instructor
Joined: Jun 2004
Posts: 155
Likes: 1
From: Melbourne Florida
have you tried to replace the EST? They do go bad and control timing. They are electronic and since it does control your timing I would suggest going through the test on it. Does it throw any code 42 with the EST wire connected? If you do replace it make sure you use enough thermal compound on it as it uses distributor base as a heatsink to keep temperature of the EST module lower. Module is located in the distributor on my 84. I hope this helps a little.
Woody
Woody
Thread Starter
Melting Slicks
Joined: Jan 2008
Posts: 2,065
Likes: 1
From: Jasper Texas
The car doesn't throw any codes with the wire plugged in. The only two things I've tried replacing is the esc module and coolant temp. sensor. No dice on either of those.
I have noticed one other things since this problem started, I find it interesting to say the least.
This only applys when the wire is connected: The tach gets a little jumpy when cruising. i might be running at 2600 rpms and then it'll spike up to 3100 like 1/2 a second, then come down. I've also revved the car a couple of times and noticed the tach fall way behind, like its at 800, when I'm at 3000+. These occurances, I've noticed, are very rare, and only happen with the timing wire plugged in. I'm really starting to wonder if my distributor itself is in failing condition, guess we'll find out tomorrow!
I have noticed one other things since this problem started, I find it interesting to say the least.
This only applys when the wire is connected: The tach gets a little jumpy when cruising. i might be running at 2600 rpms and then it'll spike up to 3100 like 1/2 a second, then come down. I've also revved the car a couple of times and noticed the tach fall way behind, like its at 800, when I'm at 3000+. These occurances, I've noticed, are very rare, and only happen with the timing wire plugged in. I'm really starting to wonder if my distributor itself is in failing condition, guess we'll find out tomorrow!
Safety Car
Joined: Oct 2007
Posts: 3,816
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From: :45 minutes from everywhere / E-I-E-I-O
I had one of these once, on an '02 bowtie 1 ton 5.7 (bought new, happened at 130k). Started out showing a quick stumble, then wouldn't do it again. Couple of days later, again. Then again, more frequently, but then I noticed it happened ONLY when the tranny shifted. Finally light a code after 2 weeks. Took it to the dealer, and they pulled the distributor, and showed me the shaft bore worn out-of-round. Only time it ever missed was at shift points.
Thread Starter
Melting Slicks
Joined: Jan 2008
Posts: 2,065
Likes: 1
From: Jasper Texas
I've thought about that also, Have a new distributor here at the house. 
I guess I can't technically say the car runs 100% with the wire disconnected. on a cold start, it idles at 6-700 rpms for about 20 seconds before the idle comes up to 900 or so in park. It hits a flat spot from time to time when driving, Like when I make a turn and hit the gas, it doesn't respond for a second or so. I guess this is too be expected with the computer not able to advance timing though. The car has yet to stall, buck, or hunt on me at idle with the wire disconnected though.
Also wanted to say that whatever the problem is, its not related to the knock sensor or esc module. Unplugging those with the est wire plugged in gives me the same results as having everything hooked up.
How much shaft play should the distributor have with the hold down bolt loosened?
I guess I can't technically say the car runs 100% with the wire disconnected. on a cold start, it idles at 6-700 rpms for about 20 seconds before the idle comes up to 900 or so in park. It hits a flat spot from time to time when driving, Like when I make a turn and hit the gas, it doesn't respond for a second or so. I guess this is too be expected with the computer not able to advance timing though. The car has yet to stall, buck, or hunt on me at idle with the wire disconnected though.
Also wanted to say that whatever the problem is, its not related to the knock sensor or esc module. Unplugging those with the est wire plugged in gives me the same results as having everything hooked up.
How much shaft play should the distributor have with the hold down bolt loosened?
Safety Car
Joined: Oct 2007
Posts: 3,816
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From: :45 minutes from everywhere / E-I-E-I-O
What was worn was the INTERNAL shaft, that the rotor sits on top of, and that's connected to the drive gear on the bottom. That shaft turns inside the distributor, as the distributor sits in the intake mount hole.
If you can create your tune problem (the spark timing control connected, vs. UN-connected), then it shouldn't be too tough to solve that part of the problem.
Since the thing changes timing one way or the other when it is plugged in, then one of 2 things is wrong:
1) The timing is already too far retarded (but still runs), and the controller is further retarding it to the point where it doesn't run, OR
2) The voltage is not right in the connector, or it is reversed polarity somehow, and the opposite of #1 is happening.
ed. Whatever your mechanic says tomorrow, see if you can get him to write it down. I think quite a few of us would like to hear this...
Last edited by schrade; Jul 21, 2008 at 01:25 AM.
Thread Starter
Melting Slicks
Joined: Jan 2008
Posts: 2,065
Likes: 1
From: Jasper Texas
Yep, can't wait to see what he finds. But you say the distributor shaft should have no play...When I loosened the bolt to turn it the other day, I could wobble it alittle side to side...not a whole lot, but definitely noticeable and with little effort.
Le Mans Master
Joined: May 2004
Posts: 5,866
Likes: 60
From: Hellinois
Finalist 2020 C4 of the Year - Modified
Read Scrade's post again,,, with the holddown bolt loose and holding the distributor you are moving the WHOLE distributor! Your problem MAY be with the internal shaft which CANNOT be checked without at least removing the cap. I really mean no disrespect here but I can tell from your posts that you do need to turn the car over to someone who has experience. I also agree with Scrade,, let us know what the mechanic finds.
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Thread Starter
Melting Slicks
Joined: Jan 2008
Posts: 2,065
Likes: 1
From: Jasper Texas
I know what he was suggesting to check is different from what I was doing. I was just wandering if I should be able to move the distributor or not, that's all.
Taking it out to the mechanics now. Hoping for the best, expecting the worse (whatever it may be).
Taking it out to the mechanics now. Hoping for the best, expecting the worse (whatever it may be).
Thread Starter
Melting Slicks
Joined: Jan 2008
Posts: 2,065
Likes: 1
From: Jasper Texas
I'm guessing its going to be something simple; static timing being off sounds like a good possibility. What confused me about the whole thing is how well it ran with the est wire disconnected compared to connected. This got me going in the wrong direction, looking for something that was over advancing timing, like the esc module. I kept thinking it couldn't be something after the esc circuit, because it wouldn't run good even with the wire off, but now I'm starting to think differently. The only thing I haven't ruled out in the computer side of the system is the ecm itself, which appears to check out good (throws correct codes) and my mechanic said wouldn't advance timing itself.
I'm getting a new belt tensioner in the mail either tomorrow or wednesday; when I take that out to him, we'll discuss and trouble shoot this timing issue.
I'm getting a new belt tensioner in the mail either tomorrow or wednesday; when I take that out to him, we'll discuss and trouble shoot this timing issue.
Racer
Joined: Jul 2006
Posts: 315
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I have an 86' that had that symptom.
Here is what happened. The harmonic balancer had begun to slip. In looking back at my eariler photos, I can see that, but at the time I did not know what I was looking at. The balancer got worse until it had moved back against the timing chain cover and made a squealing noise from contact. After I changed the balancer, I checked the timing and found that the engine's base timing was just over 13 degrees. On the old balancer it was showing 6 degrees at the same engine position (the last time I set the timing, before the balancer had slipped completely). Resetting the timing to the correct 6 degrees caused a massive improvement in my engine's idle quality and cured the stutter/stumble problem.
I took some phots of the replacement, you can see them here:
http://members.***.net/effergyvette/..._balancer.html
Here is what happened. The harmonic balancer had begun to slip. In looking back at my eariler photos, I can see that, but at the time I did not know what I was looking at. The balancer got worse until it had moved back against the timing chain cover and made a squealing noise from contact. After I changed the balancer, I checked the timing and found that the engine's base timing was just over 13 degrees. On the old balancer it was showing 6 degrees at the same engine position (the last time I set the timing, before the balancer had slipped completely). Resetting the timing to the correct 6 degrees caused a massive improvement in my engine's idle quality and cured the stutter/stumble problem.
I took some phots of the replacement, you can see them here:
http://members.***.net/effergyvette/..._balancer.html
Thread Starter
Melting Slicks
Joined: Jan 2008
Posts: 2,065
Likes: 1
From: Jasper Texas
My problem shouldn't be with the balancer slipping. I didn't set timing to balancer marks, I haven't messed with timing since I bought the car. It didn't have this problem back then. The problem has been one thats gotten progressively worse. I had two leaky injectors, replaced them and engine runs much smoother, no smoke out of the exhaust, but still the idle issue is there.
I talked to the mechanic today. He's going to check into the timing tomorrow. I'm really thinking that either the distributor itself is shot, or something inside it has taken a dump or is out of adjustment.
Knock sensor ok, esc module ok, wiring to ecm ok. TPS ok, IAC ok, MAF ok, Coolant temp. sensor ok, O2 sensor ok, ecm checks out (throws and stores codes), plugs ok, wires ok, injectors ok, fpr ok, fuel pump ok. Can't find a vac. leak to save my life. Lots of good things there!
I think I've got it narrowed down to either the timing being off, distributor causing timing to be off, or...something internal
So, I just want to do some learning here: Why would the timing being off or distributor being messed up make the car run so bad with the est wire connected, but ok with it disconnected? Shouldn't the car still run poor with the est disconnected?
I talked to the mechanic today. He's going to check into the timing tomorrow. I'm really thinking that either the distributor itself is shot, or something inside it has taken a dump or is out of adjustment.
Knock sensor ok, esc module ok, wiring to ecm ok. TPS ok, IAC ok, MAF ok, Coolant temp. sensor ok, O2 sensor ok, ecm checks out (throws and stores codes), plugs ok, wires ok, injectors ok, fpr ok, fuel pump ok. Can't find a vac. leak to save my life. Lots of good things there!
I think I've got it narrowed down to either the timing being off, distributor causing timing to be off, or...something internal
So, I just want to do some learning here: Why would the timing being off or distributor being messed up make the car run so bad with the est wire connected, but ok with it disconnected? Shouldn't the car still run poor with the est disconnected?
Safety Car
Joined: Oct 2007
Posts: 3,816
Likes: 0
From: :45 minutes from everywhere / E-I-E-I-O
Yeah. The timing controller doesn't change timing that much, that would put it into the no-run timing range.
There's probably more than one thing wrong here. Make sure the mechanic lets you know what he's found, BEFORE he starts replacin' parts ***** - nilly
. And show you the broken stuff.
There's probably more than one thing wrong here. Make sure the mechanic lets you know what he's found, BEFORE he starts replacin' parts ***** - nilly
. And show you the broken stuff.
Thread Starter
Melting Slicks
Joined: Jan 2008
Posts: 2,065
Likes: 1
From: Jasper Texas
That's what I was thinking, maybe I still have a vac. leak or a bad ground hiding somewhere also.
I should clarify how the car runs with the wire connected vs. disconnected
Connected: won't run under its own power when cold, bucks and hunts at idle even when warm. Runs great with throttle. If in gear and sitting still, could die at any moment. No check engine light.
Disconnected: Idles, not perfect, but darn close to it when cold, and even better when warm. Occasional flat spot when trying to accelerate out of turns and such. Noticeable lack of power via butt dyno. Never dies or tries to stall.
Basically, the problem only shows itself at idle. Base timing, right?
I should clarify how the car runs with the wire connected vs. disconnected
Connected: won't run under its own power when cold, bucks and hunts at idle even when warm. Runs great with throttle. If in gear and sitting still, could die at any moment. No check engine light.
Disconnected: Idles, not perfect, but darn close to it when cold, and even better when warm. Occasional flat spot when trying to accelerate out of turns and such. Noticeable lack of power via butt dyno. Never dies or tries to stall.
Basically, the problem only shows itself at idle. Base timing, right?
Thread Starter
Melting Slicks
Joined: Jan 2008
Posts: 2,065
Likes: 1
From: Jasper Texas
He just got back in town yesterday from the races. When I talked to him, he said its probably a simple timing issue. Hopefully he'll have it ready tomorrow or sunday.
Car is also getting an oil leak fixed, new belt tensioner installed, and throttle cable adjusted so I can reach WOT along with fixing the timing issue.
Car is also getting an oil leak fixed, new belt tensioner installed, and throttle cable adjusted so I can reach WOT along with fixing the timing issue.
Thread Starter
Melting Slicks
Joined: Jan 2008
Posts: 2,065
Likes: 1
From: Jasper Texas
Just got the call from the mechanic. Said car is ready.
Timing was very advanced, he pulled it down to 10 and said its running much better. I'm heading out to get it now, I'll let y'all know how it goes.
Timing was very advanced, he pulled it down to 10 and said its running much better. I'm heading out to get it now, I'll let y'all know how it goes.
