Fast idle - after top end rebuild & LWF install
#1
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From: Calgary, Alberta, Canada
Fast idle - after top end rebuild & LWF install
Started her up a couple of nights ago after doing the top end (valve guides and valves, thx SteveW) and LWF and clutch.
But I only let it run for a few seconds, as the idle is was about 3000 rpm and if my info is correct, the 20 minute break-in should be at 2000 rpm (although maybe that's just to set piston rings - which I did not replace).
Anyone have any ideas why the fast idle, or what I can check / do about it?
Blipping the accelerator pedal didn't make idle drop (but it did give my wife a nice blast of exhaust in her face, straight of the cats, from 15 feet away... she was not amused).
I have checked the throttle linkage; the cable is under no tension and the throttle actuator arm is fully closed in resting position. Durametric confirms the throttle angle is closed prior to startup, and realtime readings shows response to pedal input. So I'm pretty sure the throttle isn't stuck open.
The only Durametric error code is low voltage (107 & 108 IIRC), might be the new voltage regulator / brush assembly (old brushes were worn).
No misfire codes, luckily - I had set the flywheel reference sensor to 1.0mm but learned belatedly that for the RS flywheel it is 0.8mm (+/- 0.2mm). So doubt if the flywheel is the issue - unless the ECU somehow needs to "learn" the new RS flywheel?.
I didn't clean the ISV as it was done thoroughly about 2 years ago, and idle was fine when I started the teardown. I've only every heard the ISV implicated in rough / wandering idle, not in steady idle that's just way too high.
All wiring is connected, and reasonably sure I got the vacuum lines connected right. Could a goof up in the connections or a vacuum leak cause the fast idle?
Any ideas / hints / suggestions? Should I just run the 20 minute break-in at 3000 rpm and see if it settles out?
TIA for any and all help
cheers/bx
But I only let it run for a few seconds, as the idle is was about 3000 rpm and if my info is correct, the 20 minute break-in should be at 2000 rpm (although maybe that's just to set piston rings - which I did not replace).
Anyone have any ideas why the fast idle, or what I can check / do about it?
Blipping the accelerator pedal didn't make idle drop (but it did give my wife a nice blast of exhaust in her face, straight of the cats, from 15 feet away... she was not amused).
I have checked the throttle linkage; the cable is under no tension and the throttle actuator arm is fully closed in resting position. Durametric confirms the throttle angle is closed prior to startup, and realtime readings shows response to pedal input. So I'm pretty sure the throttle isn't stuck open.
The only Durametric error code is low voltage (107 & 108 IIRC), might be the new voltage regulator / brush assembly (old brushes were worn).
No misfire codes, luckily - I had set the flywheel reference sensor to 1.0mm but learned belatedly that for the RS flywheel it is 0.8mm (+/- 0.2mm). So doubt if the flywheel is the issue - unless the ECU somehow needs to "learn" the new RS flywheel?.
I didn't clean the ISV as it was done thoroughly about 2 years ago, and idle was fine when I started the teardown. I've only every heard the ISV implicated in rough / wandering idle, not in steady idle that's just way too high.
All wiring is connected, and reasonably sure I got the vacuum lines connected right. Could a goof up in the connections or a vacuum leak cause the fast idle?
Any ideas / hints / suggestions? Should I just run the 20 minute break-in at 3000 rpm and see if it settles out?
TIA for any and all help
cheers/bx
#4
Yeah, 2000 is too low, that is why I previously commented your 3000 RPM "idle" is perfect to break in all the moving parts.
Could be a number of factors, i am sure Steve will help you out. Hard to diagnose remotely though - and if you are not throwing any codes except for low voltage (charge the battery to get you through the breakin if the charge circuit is not working), its has to be something that sensors will not pick up.
Cheers,
Mike
Could be a number of factors, i am sure Steve will help you out. Hard to diagnose remotely though - and if you are not throwing any codes except for low voltage (charge the battery to get you through the breakin if the charge circuit is not working), its has to be something that sensors will not pick up.
Cheers,
Mike
#5
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From: Calgary, Alberta, Canada
Thx Steve & Mike, will run the break-in at 3k RPM tonight, change oil & filter, check for metal chunks and vacuum leaks etc, and will call you tomorrow Steve.
You guys rock , it is safe to say I could not have got this project to this point without your generous contributions of time and expertise to the RL community and my own noob questions. I am seriously grateful and hope I can return the favour someday, or at least pay it forward.
Cheers/Brian
You guys rock , it is safe to say I could not have got this project to this point without your generous contributions of time and expertise to the RL community and my own noob questions. I am seriously grateful and hope I can return the favour someday, or at least pay it forward.
Cheers/Brian
#6
Thx Steve & Mike, will run the break-in at 3k RPM tonight, change oil & filter, check for metal chunks and vacuum leaks etc, and will call you tomorrow Steve.
You guys rock , it is safe to say I could not have got this project to this point without your generous contributions of time and expertise to the RL community and my own noob questions. I am seriously grateful and hope I can return the favour someday, or at least pay it forward.
Cheers/Brian
You guys rock , it is safe to say I could not have got this project to this point without your generous contributions of time and expertise to the RL community and my own noob questions. I am seriously grateful and hope I can return the favour someday, or at least pay it forward.
Cheers/Brian
#7
Hey Brian,
Great see "hear" that your engine is back together and starting. As per Steve W, run it at 3000 (it will make the neighbours happy) and then just recheck Throttle position sensor, vac lines etc. I know from past experience sometimes with a visual it looks like the wires are in place but may not be fully engaged.
Keep us all informed.
Great see "hear" that your engine is back together and starting. As per Steve W, run it at 3000 (it will make the neighbours happy) and then just recheck Throttle position sensor, vac lines etc. I know from past experience sometimes with a visual it looks like the wires are in place but may not be fully engaged.
Keep us all informed.
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#8
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From: Calgary, Alberta, Canada
Hi Steven,
I put the mufflers on last night so hopefully the neighbors don't show up with torches and pitchforks when I run it this evening.
Will recheck wiring connections, and test for vacuum leaks. I already checked seating on connections for
- MAF
- throttle position (and durametric shows response to pedal inputs)
- O2 sensor
- ISV
I have to think it's something stupid I overlooked, so if I keep looking hopefully I'll figure it out.
Interest in your own project runs high... I had to resort to near violence (or at least guilt and moral suasion) to wrest the November Excellence out of my teenager son's hands last night. Let me know if you need help from my 10 thumbs...
I put the mufflers on last night so hopefully the neighbors don't show up with torches and pitchforks when I run it this evening.
Will recheck wiring connections, and test for vacuum leaks. I already checked seating on connections for
- MAF
- throttle position (and durametric shows response to pedal inputs)
- O2 sensor
- ISV
I have to think it's something stupid I overlooked, so if I keep looking hopefully I'll figure it out.
Interest in your own project runs high... I had to resort to near violence (or at least guilt and moral suasion) to wrest the November Excellence out of my teenager son's hands last night. Let me know if you need help from my 10 thumbs...
#9
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From: Calgary, Alberta, Canada
Steve, looks like I won't be calling you just yet. The break-in didn't go so well...
About 4 minutes into it I got out to check for leaks, and found the mother of all leaks - 2ft diameter puddle under the car.
It's coming from the top side, somewhere behind the varioram on the right side. Quite a lot pooled around the intakes on that side, although it is liberally sprayed lots of other places. Can't see the source, but my best guess is the oil pressure or temp sensor seals or o-ring underneath.
Now debating whether to drop the engine again, or just pull the varioram.
About 4 minutes into it I got out to check for leaks, and found the mother of all leaks - 2ft diameter puddle under the car.
It's coming from the top side, somewhere behind the varioram on the right side. Quite a lot pooled around the intakes on that side, although it is liberally sprayed lots of other places. Can't see the source, but my best guess is the oil pressure or temp sensor seals or o-ring underneath.
Now debating whether to drop the engine again, or just pull the varioram.
#10
oh that sucks......
Without removing the engine it may be difficult to clean up all of the oil. it really does get everywhere. i would also check the clamps on the oil lines,it can be easy to forget to tighten one...
Good luck, sucks to be doing this when you are so close...
Without removing the engine it may be difficult to clean up all of the oil. it really does get everywhere. i would also check the clamps on the oil lines,it can be easy to forget to tighten one...
Good luck, sucks to be doing this when you are so close...
#11
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From: Calgary, Alberta, Canada
Good point, I guess I can't just throw some cat litter back there to soak it up.
Engine drop it is, probably nearly as easy as pulling the variorum since I haven't gotten too far in the reassembly. New plan for the long weekend.
In the meantime, think I'll pick up a borescope to have a look at the leak in action and confirm the location. Great excuse to pick up a new tool that I've wished I had many times already.
Will also double check the hose clamps - but are any of the topside oil lines pressurized? I thought they were all breathers?
Sigh.
Engine drop it is, probably nearly as easy as pulling the variorum since I haven't gotten too far in the reassembly. New plan for the long weekend.
In the meantime, think I'll pick up a borescope to have a look at the leak in action and confirm the location. Great excuse to pick up a new tool that I've wished I had many times already.
Will also double check the hose clamps - but are any of the topside oil lines pressurized? I thought they were all breathers?
Sigh.
#13
Don't drop the engine. Take out the varioram. I got soooo good at taking mine out 95 convertered to varioram, I can do it with my eyes closed. It's easy, just hard the very first time.
You will be also able to check your throttle cable and cruise control connection with the varioram out.
You will be also able to check your throttle cable and cruise control connection with the varioram out.
#14
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From: Calgary, Alberta, Canada
I was leaning toward just varioram but Steven rightly pointed out that cleanup of the Exxon Valdiz would be easier with engine out.
Only a small incremental effort given that I did not get very far with reassembly - 8 bolts, 5 vac/breather hoses, 4 oil & p/s hoses and a handful of electrical plugs.
Besides, engine drops are FUN !!!
Only a small incremental effort given that I did not get very far with reassembly - 8 bolts, 5 vac/breather hoses, 4 oil & p/s hoses and a handful of electrical plugs.
Besides, engine drops are FUN !!!