rough running

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Steve E J
Posts: 33
Joined: Fri Mar 18, 2011 10:47 am
What year is your cabby?: 1988
Do you own a Cabriolet?: Yes
Location: IL, USA

rough running

Post by Steve E J »

I just started driving my cabby. It's been sitting a year or two now. I had a problem today where I went somewhere and turned off my cabby for about two hours and when I started it up again it was idling lower than usual and if the gas pedal was between 25% and 70% it would run roughly and not accelerate. If the gas pedal was only pushed a little bit(below 25%) or a lot(above 70%) it would increase engine speed normally. I stopped my engine and restarted while at a stop sign and it ran normally after that. Any tips?




and a pic for good measure:(yes that's the dashboard on the ground, don't worry I have it in now)
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PDX Cabby
The Living Bentley Manual
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Joined: Tue Dec 30, 2003 12:51 am
What year is your cabby?: 1985
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Location: Portland, OR
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Re: rough running

Post by PDX Cabby »

i just recently brought mine back after sitting in pieces for a few years as well...

as for the gremlin, i wouldn't worry about it right away unless it happened a second time. It kinda sounds like a vacuum leak though.

After sitting, there's a lot of gunk build up in the fuel system, and a lot of other parts as well. there's going to be some maintenance required to get things running perfect.
85 Cab - 1.9L 8v, g-grind, euro dual downs to TT race w/ Borla, VWMS fuel dizzy, 2H tranny with 5th gear swap, TT short shift, FK 60/40, 15" BBS RA, rear disks... begging for boost...
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gull
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Re: rough running

Post by gull »

What year? Is this a CIS car?

My experience with CIS cars is they frequently run rough when started hot. Both of mine do it. If I shut them down while they're hot and try to start them within an hour or so, they run rough and won't idle at first. If I hold the revs over 2000 for about 30 seconds they smooth out and run OK after that. I suspect some kind of CIS vapor lock issue.
VW fan who fell to the Honda side of the force
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Steve E J
Posts: 33
Joined: Fri Mar 18, 2011 10:47 am
What year is your cabby?: 1988
Do you own a Cabriolet?: Yes
Location: IL, USA

Re: rough running

Post by Steve E J »

thanks for the help, it is a 1988 cis.

This was the second time it happened, the first time I was driving on the highway for about a half-hour like that, it didn't smooth out at all. I stopped at a gas station and filled up and it ran fine after that. My car is getting low on fuel again(just touching the red) so it might be fuel pump related?
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gull
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Joined: Sun Feb 19, 2006 6:30 pm
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Re: rough running

Post by gull »

Steve E J wrote:thanks for the help, it is a 1988 cis.

This was the second time it happened, the first time I was driving on the highway for about a half-hour like that, it didn't smooth out at all. I stopped at a gas station and filled up and it ran fine after that. My car is getting low on fuel again(just touching the red) so it might be fuel pump related?
Sounds like your in-tank fuel pump has probably had it.
VW fan who fell to the Honda side of the force
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Calimus
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Re: rough running

Post by Calimus »

when it's running rough (if it does it again), pop the hood and listen for the frequency valve (buzzing noise coming from around the airbox area). These can sometimes fail intermittently and it will cause a crappy idle and odd running when it's not behaving. One of many things to check on a CIS car.

As mentioned, the in tank pump. It can also wig out intermittently. It's located under the rear seat. Just pop the seat out (two screws are all that's keeping the seat in place) and then there is an access panel. Remove that (3 screws I think) and you should be able to hear it running clearly) You can also pull the pump out and just have someone cycle the key to the "on" position and not start and it should kick on to "prime" the system. If it doesn't, it's prollie Kaput.

Also, don't discount a clogged fuel filter. If some trash got into it, it could block flow and then after restarting the car, it could shift and allow better flow.

Just a few things off the top of my head.
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Steve E J
Posts: 33
Joined: Fri Mar 18, 2011 10:47 am
What year is your cabby?: 1988
Do you own a Cabriolet?: Yes
Location: IL, USA

Re: rough running

Post by Steve E J »

Thanks guys.

I haven't had it happen to me yet again. Might of just been dirty/bad gas clogged fuel line, sticky valve somewhere, etc...
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