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Intermittent CEL, poor mileage.

Old 07-09-2006, 07:02 PM
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Default Intermittent CEL, poor mileage.

On my 96, I have been getting since I owned the car (and even since the previous dumbass owner had it) an intermitent CEL. The code is a general emissions component failiure, nothing specific at all (I dont remember the EXACT P code given by the Actron). I checked the lines and inspected the charcoal cannister for the evap system but found nothing out of order. I tried to check the filter on my purge valve but mine is perfectly sealed into one component. ANd I dont know if its related, but gas mileage is **** poor. I have replaced the O2 sensor (ACDelco of course) and pcv valve, fuel filter is new. I also cleaned out the EGR valve but the valve still moved up and down easily so I didn't do much of anything. Could the EGR valve still be a link to my failiure? Or just get a new purge valve?

I dont know how "sluggish" in performance it is since I never driven another SSEi so I can't really benchmark, but with a supercharger I expect a bit more oomph when accelerating, or mayby I expect too much.

But one thing is for sure, I have an intermittent CEL and its guzzling gas like a drunkkard at a bar, and with todays gas prices and my mom'* stupidly heavy driving this HAS to be fixed asap. Im running out of ideas (and time!) and need your help.
Old 07-09-2006, 07:16 PM
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I'd start by removing all six spark plugs & see how they look. Keep track of which cylinder they come from.
Old 07-09-2006, 08:11 PM
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I was getting a rash or random misfire codes, giving me that sluggish performance also, which ended up being the coil packs. fwiw.

I think the exact code might help lead you in the right direction.
Old 07-11-2006, 06:34 PM
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P1406 Manufacturer Controlled Auxillary Emissions Control

Thats the code I pulled from the Actron CP9135. ITs very general and does not point me to a specific problem.

Stock plugs and wires were installed at 123k, I dont think there is any indication of a misfire whatsoever and I dont have a misfire code.

Any other ideas?

Edit: I found out the code is the EGR valve, however the pintle moves up and down easily and I have reconnected it a few times, could it still be the culprit or something else? And would a bad EGR give me poor mileage?
Old 07-11-2006, 07:03 PM
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The poor mileage is why I thought you should check the plugs. IMHO it'* the best way to get an idea what'* going on in the combustion chamber. I don't know if the egr will effect MPG. How bad is the mileage?
Old 07-11-2006, 07:16 PM
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17-18 MPG, mixed city/highway driving. On my 93, I get 23-25 MPG in similar driving conditions. Yea its an SE, but I should expect the numbers to be a bit closer.

I can only have the plugs checked on the weekend when the motor is cool and when I have time.
Old 07-11-2006, 08:39 PM
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troublecodes.net says 1406 is the egr position sensor, if that helps; usually mounted on top of the egr vlave to monitor the psoition of the pintle.

If your egr is vacuum triggered,my olds is the digital variety, then check the vacuum line to the egr from the regulator and from the regulator to the main line. Problem can also be caused by a sticky vacuum regulator. Again, this is if you have this equip, i'm not that familiar with the bonne'* but do try to help.
Old 07-13-2006, 03:10 PM
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Mine is digital. There wasn't much to clean out when I took it out, do I have to completely take it apart and rebuild it?

ALso I just tanked my car, 15 MPG! This is getting ridiculous. Can a bad hub bearing or a need for an alignment be a cause for my poor mpg? Because I need to do both.

I still need help!
Old 07-13-2006, 03:38 PM
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Wheel bearing wouldn't effect mpg unless it'* about to seize. If it'* not pulling to one side you can rule that out. Wheel alignment would have to be off a mile to have any affect on mpg.

You really don't want to check those plugs do you? Two plugs darker than the others could indicate a weak coil.

Seems like the most likely things to affect mpg would be o2 sensor, temp sensor, MAF sensor & air filter. Are you hearing any pinging under load?
Old 08-03-2006, 01:58 PM
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Here are the pics of the plugs. Ive replaced them with a new set of TR-55'*. These old plugs only have several thousand miles on them so they are still pretty good. The plugs look fine to me...

http://www.clanmob.net/hosted/bonnev...c/DSC00732.JPG
http://www.clanmob.net/hosted/bonnev...c/DSC00733.JPG
http://www.clanmob.net/hosted/bonnev...c/DSC00735.JPG

I dont hear any pinging under load. And I just replaced the EGR valve with a used but working one so hopefully that should get rid of the CEL.

So what else could be causing my poor gas mileage?

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