Fuel Issue???

[mazdags94]

I just finished a complete head gasket job w/ new timing belt, serpentine belts, water pump, tensioner, pulleys, lower mileage cylinder heads that were decked and valve checked, and some other things. You can check my worklog for pics if you'd like. The engine is a 1.8L K8 V6. Anyways, she started up great after the job without the CEL coming on. However, I do have a problem. After starting and running for 5mins or so (when warm) the exhaust smells very fuel rich and the color is somewhat white. If revved, the smoke turns black and then back to a white cloud. It doesnt smell like sweet and it doesnt look like the color of burning oil (blue). I pulled the plugs and found them each to be black, even though those were replaced as well (NGK iridiums). One seemed to smell a little more like fuel than the others (i believe cylinder #1; the back left plug when facing the engine in front of the car).

It seems as though something is telling the fuel system to dump more fuel in the cylinders than needed bc the engine doesnt run rough at all and its not misfiring.

What could be causing this? Is there anything that I could change or adjust to correct this (i.e. TPS, VAF, Temp sensor?)

Any help on this would be greatly appreciated. Thanks.

[93SOHC]

coolant temp sensor controls fuel based on temp of engine. I had the exact problem on a BP protege and $5 later it was solved

[mazdags94]

Thanks a lot, I'll give that a try. Hopefully it works. I was also gonna try new O2 sensors as well. I'll let you know how this works out.

[mazdags94]

Did some searching and tried to let the car run for about 15-20mins to let the ECU "learn" the engine to see if would spit any codes back to me...... and nothing. We just got our first snowfall and its about 28 degrees Farenheit, and now the idle jumps between 1500 and 2000 in two second intervals. I'm guessing a vacuum leak cuz there are a couple holes i need to plug off. The fuel problem is still there though. Disty maybe, aka, not getting enough spark----> not getting enough fuel????? STill trying.

[mazdags94]

One more thing... is there any way to adjust the timing without having to tear the car down to the timing belt? I mean, only if it's off one or two teeth.

I assume it would be very apparent if the timing is off but i was just wondering this for future reeference.

I could be wrong though....

[400bird]

There really is not any way to adjust the timing belt without tearing the engine down to the belt and moving it, unless you have adjustable cam gears.
But, if the timing belt was off a tooth or two you would know it by how terrible the engine runs...

The ignition timing is another story.

[mazdags94]

OK. so i replaced the coolant temp sensor... but then I saw that there was another one... and possibly a third??? The one I replaced is the one nearest to the fill cap on the left side of engine ( when looking at it from the front). There is another one right above the one I replaced (which I believe is a single wire, black harness) and another with a single wire that is located between the right and left cyl heads under the main coolant line (which also has a black harness). The one I replaced has a two prong connector with a grey harness. I'm assuming I replaced the right one. The old one i took out looks pretty crappy (cost me $30 though). I'm throwing a code 9 now but I haven't run the car to reset the ECU. Is this necessary in order to clear the code? I am assuming so. I also flushed out the system ( which was disgustingly brown) with some Prestone Radiator Flush (for "neglected" coolant systems) and it seemed to do a great job. Now I have some fresh coolant in there so I hope this will fix the fuel-rich issue I'm having.

I have started it for a short period prior to flushing the system but after replacing the sensor and it was still the same. WIll the ECU have to be reset before it will potentially work? Also, if this doesnt solve the issue, could it be possible that my ignition timing is off in the disty? I attempted to adjust my TPS and both bolts BROKE OFF !!!!!!

[Mad Cow]

Unplug the battery and hold the brake pedal down for a few seconds, that resets the ECU. Do that and try again.

[mazdags94]

Here is video of what I'm dealing with...




And this is how she starts up.... (I added more oil right after shooting this video, FYI, as you can hear the cams)