Author Topic: Runs rough, surges...aaargh! (Read 4417 times)

Jettage1 · « **on:** November 26, 2008, 04:16:19 pm »

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!

burn_your_money · « **Reply #1 on:** November 26, 2008, 04:26:05 pm »

Quote from: "Jettage1"

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.

Smokey Eddy · « **Reply #2 on:** November 26, 2008, 04:37:30 pm »

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:

burn_your_money · « **Reply #3 on:** November 26, 2008, 04:50:26 pm »

Check for air leaks, both into the fuel line, and loose hose/boost connections

Jettage1 · « **Reply #4 on:** November 26, 2008, 04:59:37 pm »

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...

burn_your_money · « **Reply #5 on:** November 26, 2008, 05:25:41 pm »

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

Jettage1 · « **Reply #6 on:** November 26, 2008, 05:53:55 pm »

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!

maxfax · « **Reply #7 on:** November 26, 2008, 10:52:47 pm »

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...

Smokey Eddy · « **Reply #8 on:** November 27, 2008, 12:25:23 am »

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!

Jettage1 · « **Reply #9 on:** November 27, 2008, 05:00:21 am »

Thanks everyone... I'll let you know how it works out! I hope it's that simple too.

vanbcguy · « **Reply #10 on:** November 27, 2008, 09:00:47 am »

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!!

Jettage1 · « **Reply #11 on:** November 28, 2008, 09:08:30 am »

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?

maxfax · « **Reply #12 on:** November 28, 2008, 09:19:26 am »

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:

Quote from: "Jettage1"

BTW, did I see you on the vortex talking about SVO?

Yeah, you probably have...

dillenger1 · « **Reply #13 on:** November 29, 2008, 03:11:51 am »

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!

Jettage1 · « **Reply #14 on:** November 29, 2008, 04:58:56 am »

Yep, that's the one... Maybe I need to check the others to be sure...