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Rough running after doing some engine work...

Old Jun 15, 2005 | 07:13 PM
  #1  
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Default Rough running after doing some engine work...

Hi All,



I have completed a fairly large bit of work on my car, an 86.0 5 speed. It started no problem but seems to be running pretty poorly. The list of replaced items include...

Motor mounts, steering system, Pan gasket, oil pickup seal, Cam cover gaskets, all rubber under intakes and intake sleeves, all vacuum lines under intakes, plug wires (Kingsborn), Dist cap+rotors, T-stat and seals, new 24 lbs ford injector set (summmit) and of course fluids. (and more I have forgotten)

I had the intakes powder coated...

The symtoms are that it idles rough and stalls easily. It revs slowly but still fairly smoothlt. It has no power (sounds like a VW bug and has about as much power). At first I smelled some sulpher like smell but now I do not notice any one smell over the others... I spilled some orange coolant when filling and the smell of that burning off the exhaust is really potent.

Last fall the MAF + O2 were replaced and the WP/TB job was done.

The powder coat was done on the intake runner sealing surfaces too.... so I used the permatex "right stuff" black silicon to seal them to the gasket. No sealant was used on the gasket to intake port surface. I am thinking I may have a leak there. All of the joints I do not suspect. Another possibilty I was kicking around it that the fuel rail may have some Air in it??? I was told that this was unlikely since the car has ran for at least 10 minutes. It started pretty quick so I figured that the system purged itself fairly easliy.

I was wondering about any suggestons that you all may have. Any suggestions would help as I am prety much out of ideas. I have an appointment but have a week and a half until I can take it in. In the meantime I will probably take the intakes off and reseal the gasket to head surfaces. I may also try and purge the fuel system... maybe I can take the passenger side gauge plug off and pump some fuel through and collect at that point.

Any suggestion on diagnosis???

maybe I can try to pressurize the intakes and spray soapy water

Anyone if the SF Bay Area want to come over an pull their hair out with me... The car though it leaked like a sieve was running like a champ 5 months ago and now it surely is not the same car

Thanks All,

Loren Olson
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Old Jun 15, 2005 | 07:37 PM
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Start with the easy stuff... check and re-check the spark plug wires, especially if you removed them from the distributors. Sounds like you may have at least 2 out of order.
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Old Jun 15, 2005 | 08:13 PM
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Next look for a vacuum leak.
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Old Jun 15, 2005 | 08:44 PM
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Could the car run with the plug wires out of order? I will check again as anything is possible...

Vacuum leaks .... God I hope not.. as that sounds like a bunch of voodoo to me...

THanks,

LO
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Old Jun 15, 2005 | 10:34 PM
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spray something volatile on the joints and see if idle changes - if it does, the spray got sucked in....
jp 83 Euro S AT 49k
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Old Jun 16, 2005 | 12:23 AM
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The car will run with two wires swapped, but quite poorly. You'll also be able to smell unburnt fuel.
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Old Jun 16, 2005 | 01:40 AM
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Originally Posted by lorenolson888
Could the car run with the plug wires out of order? I will check again as anything is possible...
THanks,

LO
Yes. BTDT.
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Old Jun 16, 2005 | 01:44 AM
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Loren:

I can come over and help you check it out weekend after this one. It does sound like a vacuum leak. The manifold should be done without sealant, I believe, so unless you mooched the gasket, I wouldn't worry about that. Maybe we can locate the problem.

I had a couple of plug wires mixed and the car ran with a decided miss. That should be obvious.

As many times as I have replaced injectors, I've never encountered an air in the fuel lines/rails issue. Air gets pushed out by the fuel.
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Old Jun 16, 2005 | 01:49 AM
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any chance the throttle cable is not getting the plate to the wot position? could the maf have somehow been damaged? is it plugged in? any rags left in the intake? sorry, to sound insulting, just possible items that may have been over looked. can't think of much else at the moment.
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Old Jun 16, 2005 | 02:24 AM
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Checking the orientation of the wires isn't hard. The timing belt covers on either side actually have the cylinder numbers on them. Look closely...they're there. The spark plugs wires (at least OEM ones) have the cylinder numbers printed on them, too.

Hope you find the culprit soon!
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Old Jun 16, 2005 | 09:43 PM
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Hi All,

Thanks for the replies....

plug wires seem good...

I am going to pull off the intakes and check the little vacuum ditribution piece.

I may have tugged too hard on it when hooking one up or something. Other that that I may have to wait for the experts... As much as that pains me.... I want to drive !!!!! and show it off to my buds.

Thanks and Bill I will PM you...

LO
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Old Jun 16, 2005 | 09:53 PM
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check the plug wires again....1 and 4 are easy to get reversed, and as mentioned...it'll run, but not very well. BTDT. Good luck.
JJ
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