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Engine Specific Info and Questions => IDI Engine => Topic started by: Jettage1 on November 26, 2008, 04:16:19 pm
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This is not really my week, evidently.
In addition to my newly leaking IP (see other post), today my car started running roughly and sometimes surging at higher rpms (2,800~3,000+). Idles fine and seems okay at lower rpm. The only other symptom I noticed was that maybe it was a bit more clattery on cold startup this afternoon, but that might just be a perception...
I noticed the rough running as extra vibration through the gas pedal and oddly, it almost felt a bit like it was "running away" at those times, although it always decelerated fine...
Can anyone put me on the right trail here?? If the o-ring on the cold-start advance was leaking, could it suck air & cause probs? (really wild guess here...)
Thanks!
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If the o-ring on the cold-start advance was leaking, could it suck air & cause probs? (really wild guess here...)
Thanks!
It would push fuel out, not pull air in. If the leak was bad enough, your timing would be retarded.
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well what do you mean by surges... it feels like you're pushing the nos button or what?
or is it being cut off of fuel and then gets fuel and it jumps back to accelerating or?
if it decelerates when you take your foot off he gas i don't understand what you're trying to describe by a surge.
maybe you're getting boost when you used to not and it's easier to tell with the colder weather? I dunno?
I'd love a surge in power :wink:
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Check for air leaks, both into the fuel line, and loose hose/boost connections
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First, "surge" - meaning on flat ground with throttle held steady, car begins to go faster & slower & faster & slower with me doing nothing to cause it. I suppose could be "starve" & "flow" too?? Reminds me of problems with some cars where if motor mounts are worn, the engine can set up it's own harmonic surging reaction (though I'm not suggesting that here).
I'll check for air/fuel leaks tomorrow in better light.
I also found one other thing just now... a bolt cradled between one of the lower coolant hoses and the dipstick tube. I think it came off of the bracket at the lower driver's side of the IP - it obviously just fell out today - the threads are clean and there is a clear clean round mark at the IP / bracket location. There's nothing threaded there now - was there a nut and /or washer/lockwasher? What else did I lose?!? I can try to post pics if necessary...
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There's your problem. Variable pump timing. You'll want to fix that ASAP before you bend your pump mounting brackets and then have belt tracking problems. I'd suggest not driving it.
If you have the bolt, you are missing the nut. It's tapered though. If you need it, IM me and I'll mail you one. The dealer should have it though if you need it ASAP
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Thanks Tyler. I'm glad that bolt got caught there - seeing where that bracket is under the pump, it would have been a long time before I figured out the bolt was missing... Wonder how long it had been loose?!? Jeez.
I'll check with the dealer on Friday, as I do need the car as soon as I can. If I get stuck, I'll get in touch with you - thanks for your offer!
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If you have no luck with the dealer and need one quick, I've probably got a couple of those things around here..... I'm 45 mins northwest of Harrisburg, and am in Selinsgrove/Middleburg area about every other day...
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oh wow. A floppy pump would give you some interesting fueling.
nice one! probably a smaller problem than you had hoped for!
Yayyy another solved!
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Thanks everyone... I'll let you know how it works out! I hope it's that simple too. :D
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I just went through exactly the same thing on my car... That bolt was outright missing when I bought the car and I'd had some weird surging problems. It had some really bad spots - just off idle it had a small range that was totally undrivable, once it started surging it would just get worse and worse... Shortly thereafter one of my injection lines snapped off too...
I didn't end up using the "proper" nut/bolt combo, I popped a bolt through from the back so it's acting like a stud, and then I just popped a nut on the front. I couldn't believe how much smoother my car started running!!
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vanbcguy - thanks for the confirmation of the symptoms... I'll be glad to get it fixed...
maxfax - thank you for the offer... I'm in the Lancaster (Lititz) area, and with my current schedule decided to just order the missing parts...they'll be in on Tuesday, which should be soon enough I guess. I discovered there's a tapered nut, a bushing, and a spring washer, none of which I have anymore :roll: BTW, did I see you on the vortex talking about SVO?
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Good deal.. Doesn;t sound like you're gonna have to wait for the little Kraut to bring the thing over in his row boat... :wink:
BTW, did I see you on the vortex talking about SVO?
Yeah, you probably have...
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Are we talking about the bottom bolt on the injection pump support/because ive run with that bolt completely out (for adjustment)If the other three mounting plate bolts are tight,that thing wont go anywhere!
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Yep, that's the one... Maybe I need to check the others to be sure...
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Uber Bodge coming up. Perhaps one of the cones out of a bicycle axle with a suitable bolt might do? :?
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Are we talking about the bottom bolt on the injection pump support/because ive run with that bolt completely out (for adjustment)If the other three mounting plate bolts are tight,that thing wont go anywhere!
I THOUGHT it was fine - you couldn't really see the pump moving or anything, but at certain RPM ranges the pump would get a harmonic going on and start to dance. The more advanced my timing was the easier it was to trigger the surging behavior, but with the timing retarded a bit the car was perfectly drivable. But like I said, once I dealt with that bolt I couldn't believe the difference!
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Steve, I've been following your thread & was perplexed by this surging you were experiencing. Then, last Friday, mine started to do the same thing. I checked the IP bolts & all were snug. It still surged. Today I decided to take a peak in the the light of day. Sure enough, two of the IP bracket bolts were backed off & the pump would get into a visible harmonic pattern. I snugged the bolts back up as best I could & it seems to be better. Any recommendations on tools that can reach those two bolts with the IP still in place?
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socket and extension?
which are we talking about?
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Steve, I've been following your thread & was perplexed by this surging you were experiencing. Then, last Friday, mine started to do the same thing. I checked the IP bolts & all were snug. It still surged. Today I decided to take a peak in the the light of day. Sure enough, two of the IP bracket bolts were backed off & the pump would get into a visible harmonic pattern. I snugged the bolts back up as best I could & it seems to be better. Any recommendations on tools that can reach those two bolts with the IP still in place?
Are you refering to the 2 bolts behind the IP?
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Two bolts that hold the IP bracket to the block, underneath the IP. The bracket itself and the IP interfere with getting a 3/8" socket in there properly. I got a 1/4" in there, but who trusts the torque put out by a 1/4" driver?
The good news is that it starts easier. I'm hoping that fuel economy will be more in line with what I expect. Who knows how long the bracket has been loose? I do know that the IP was replaced about 3 months before I ever got the car.
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Crescent or ess spanners will get you at what lurks behind the I.P.
A must for when the water pump dies. :twisted:
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Ballet dancing transvestites??????????????????? :?
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You don't get the Royal Variety Performance your way then? :lol: