Author Topic: Rough idle & lots of smoke  (Read 6624 times)

April 16, 2010, 04:33:21 pm

spdrace11

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Rough idle & lots of smoke
« on: April 16, 2010, 04:33:21 pm »
Well i have a 1991 VW jetta coupe.  It's a 1.6 N/A and i recently changed a timing belt and water pump.  Well i had to take the IP out to change the water pump so i did have to time the IP.  Well i tuned it to the specs and made sure the timing marks were all on.  Now grayish smoke poors out of the exaust and it has a rough idle.

Now I was a tooth off when i did the timing belt initially.  I aligned the squarish block mark on the flywheel not the diamond mark initially.  I did turn the motor over and there was no blockage.  I tried starting it and it ran for about a sec then it stalled immediately.  I looked in the Bentley and realized that i used the wrong mark.  I retimed it and it now runs but like i said it smokes and idles rough.  So anyone have any suggestions??? ??? 
91 VW Jetta diesel coupe 1.6 NA 5spd, 91 Jetta 1.6 NA, 81 Caddy 1.6NA

Reply #1April 16, 2010, 05:04:36 pm

burn_your_money

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Re: Rough idle & lots of smoke
« Reply #1 on: April 16, 2010, 05:04:36 pm »
How many mm of advance did you set the pump to?

Did it sputter and stall or just come to a dead stop?
Tyler

Reply #2April 16, 2010, 06:10:00 pm

spdrace11

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Re: Rough idle & lots of smoke
« Reply #2 on: April 16, 2010, 06:10:00 pm »
How many mm of advance did you set the pump to?

Did it sputter and stall or just come to a dead stop?

83mm as in the Bentley.

Well if by sputter when i did the belt incorretly yah it just fired on one cyc then it continued to crank.  It did not come to a complete stop like something was interfering.
91 VW Jetta diesel coupe 1.6 NA 5spd, 91 Jetta 1.6 NA, 81 Caddy 1.6NA

Reply #3April 16, 2010, 07:07:38 pm

theman53

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Re: Rough idle & lots of smoke
« Reply #3 on: April 16, 2010, 07:07:38 pm »
I would try 1.00mm next. .83 is a little low for the 91   1.6L

Also it will run like crap until the air is completely out of the system.

Reply #4April 16, 2010, 11:02:17 pm

spdrace11

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Re: Rough idle & lots of smoke
« Reply #4 on: April 16, 2010, 11:02:17 pm »
I would try 1.00mm next. .83 is a little low for the 91   1.6L

Also it will run like crap until the air is completely out of the system.

How long does it take before the air is completely out of the system???
91 VW Jetta diesel coupe 1.6 NA 5spd, 91 Jetta 1.6 NA, 81 Caddy 1.6NA

Reply #5April 17, 2010, 06:04:15 am

burn_your_money

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Re: Rough idle & lots of smoke
« Reply #5 on: April 17, 2010, 06:04:15 am »
On a 91 5-10 minutes of driving (you need to get the fuel hot enough to open the fuel preheat thing on the filter) to never depending on air leaks.

Like theman53 says, try it at 1.00mm
Tyler

Reply #6April 17, 2010, 10:01:53 am

spdrace11

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Re: Rough idle & lots of smoke
« Reply #6 on: April 17, 2010, 10:01:53 am »
On a 91 5-10 minutes of driving (you need to get the fuel hot enough to open the fuel preheat thing on the filter) to never depending on air leaks.

Like theman53 says, try it at 1.00mm

Ok great thanks.  Would one of the symptoms be the rough idle or white smoke??
91 VW Jetta diesel coupe 1.6 NA 5spd, 91 Jetta 1.6 NA, 81 Caddy 1.6NA

Reply #7April 17, 2010, 02:57:26 pm

spdrace11

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Re: Rough idle & lots of smoke
« Reply #7 on: April 17, 2010, 02:57:26 pm »
Well problem solved.  I readjusted the IP to 1.00mm then drove the car for about 10-15min.  At first it spuddered and smoked really bad.  You could see the trail down the street.  Then about 10min later it just cleared up, idled nicely and had more power.  So perhaps there was some air in the system and it took time to clear out idk, but now its fine.

I might turn the pump back to 85mm to get the best economy i can though, but as of know it runs great!!
91 VW Jetta diesel coupe 1.6 NA 5spd, 91 Jetta 1.6 NA, 81 Caddy 1.6NA

Reply #8April 17, 2010, 03:27:20 pm

Rabbit on Roids

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Re: Rough idle & lots of smoke
« Reply #8 on: April 17, 2010, 03:27:20 pm »
if you retard it back to .85mm, you will probably get WORSE mileage, and it will be harder to start, than with it set at 1.00mm

Reply #9June 05, 2010, 10:44:32 am

spdrace11

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Re: Rough idle & lots of smoke
« Reply #9 on: June 05, 2010, 10:44:32 am »
if you retard it back to .85mm, you will probably get WORSE mileage, and it will be harder to start, than with it set at 1.00mm

So whats the best setting for the most efficient fuel eco??
91 VW Jetta diesel coupe 1.6 NA 5spd, 91 Jetta 1.6 NA, 81 Caddy 1.6NA

Reply #10June 05, 2010, 11:03:47 am

79rabbit4dr

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Re: Rough idle & lots of smoke
« Reply #10 on: June 05, 2010, 11:03:47 am »
So whats the best setting for the most efficient fuel eco??

run it at 1mm for two tanks, set it at .85mm for two tanks, set it at .93 for two tanks, then you tell us. I don't think there is really any magic number that will work for everyone.

Reply #11June 05, 2010, 11:53:38 am

spdrace11

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Re: Rough idle & lots of smoke
« Reply #11 on: June 05, 2010, 11:53:38 am »
So whats the best setting for the most efficient fuel eco??

run it at 1mm for two tanks, set it at .85mm for two tanks, set it at .93 for two tanks, then you tell us. I don't think there is really any magic number that will work for everyone.

Ok thats what i was looking for thanks.
91 VW Jetta diesel coupe 1.6 NA 5spd, 91 Jetta 1.6 NA, 81 Caddy 1.6NA

Reply #12June 06, 2010, 07:13:18 am

burn_your_money

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Re: Rough idle & lots of smoke
« Reply #12 on: June 06, 2010, 07:13:18 am »
The reason the 91 (and other years) take so long to bleed the air out is because of that white/yellowish valve on the fuel filter. It will recirculate the fuel (and air) back to the filter and pump until the fuel reaches a certain temperature. Once that temperature is reached then it returns the fuel to the tank. It's a horrendous design in my opinion.
Tyler

Reply #13July 29, 2010, 08:30:43 pm

dl_sledding

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Re: Rough idle & lots of smoke
« Reply #13 on: July 29, 2010, 08:30:43 pm »
The reason the 91 (and other years) take so long to bleed the air out is because of that white/yellowish valve on the fuel filter. It will recirculate the fuel (and air) back to the filter and pump until the fuel reaches a certain temperature. Once that temperature is reached then it returns the fuel to the tank. It's a horrendous design in my opinion.

Burn,

Is this idea meant to help prevent gelling in extremely cold temps?  It seems that circulating the warmer fuel around initially would help with that, until the engine is warmed and the fuel has a chance to warm as well...  Just curious.

Alex