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The 2.8L 30 valve motors (ATQ, AHA) are prone to "flooding" when cold. This condition is typically brought on after a short drive cycle on a cold engine. A classic example would be starting the vehicle cold, pulling it out of the garage, and shutting it off, attempting to start the next morning. When attempting to start cold in the a.m. the engine will be difficult to start, and run poorly if at all. This is usually caused by carbon particles (byproduct of combustion) getting stuck on the valve seats and not allowing them to seal. The reduction in compression does not provide sufficient pressure and the combustion event can not occur so fuel is unburned and the cylinders become "flooded" with unburned fuel.
This condition can be worsened if the vehicle is run on substandard fuel for an extended period. This engine is designed to run on premium "top tier" fuel. It can be run on mid-grade "top tier" fuel with reduced performance. Only "top tier" fuels have sufficient detergents to prevent the build up of carbon and fuel deposits in the injection system and combustion chambers. See toptiergas.com for more details.
If this cold start/run condition is caught in the early stages, you can disconnect the fuel pump fuse (in the fuse panel on left of dash) it should be the third fuse from the bottom (blue/15) on the first row. There is a fuse legend on the inside of the cover to confirm location. Then try cranking over the engine for some time with the accelerator pedal to the floor, possibly almost one minuet and see if it begins to catch. If so reinstall the fuse while still cranking. If it does start try and maintain the RPMs at about 2,500 until it clears up. The vehicle must be driven and allowed to fully warm-up before shutting down.
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Thanks for the response. Unfortunately, after 3 attempts using your procedure it did not start. However, such procedure did almost start the engine. Engine went beyond turnover and engine initiated combustion, but never advanced to an actual start. Also, during the 3 attempts, after approx. 45 seconds of turn over, a 'STOP' warning appeared in odometer window and then message - 'oil pressure, see manual'.
In addition, it came closest to a start during fuse removal stage. Once fuse was pushed-in, combustion was maintained, but quickly faded back to just turning over.
Your advice got me closer, but no start. Do you have additional advice?
Yes, this is the condition. If it won't keep going, you may have to remove the spark plugs dry them and try again. I have had to do this three times on severe cases.
I suggest you keep trying the described method if you are getting results, use less fuel pump fuse, and be sure to be hooked up to a jumper battery for full cranking power. Don't worry about the oil light this is normal during extended cranking.
Thanks for 2nd response. What do you mean by 'use less fuel pump fuse'.
In my original response I wrote;
"If this cold start/run condition is caught in the early stages, you can disconnect the fuel pump fuse (in the fuse panel on left of dash) it should be the third fuse from the bottom (blue/15) on the first row. There is a fuse legend on the inside of the cover to confirm location. Then try cranking over the engine for some time with the accelerator pedal to the floor, possibly almost one minuet and see if it begins to catch. If so reinstall the fuse while still cranking. If it does start try and maintain the RPMs at about 2,500 until it clears up."
So I meant, rather than "reinstall the fuse", maybe put it in only for a second or two, and remove it until it "catches" a little more, then reinstall it. It is difficult to explain. I "play" with the fuse based on my experiance to get the right combination of, cranking it enough to allow the carbon to be dislodged from the valve seats, and NOT flood the spark plugs with unburned fuel.
Hope this helps!
Your advice has just paid off!
Per your suggestion, as last resort before I called for a tow to local repair shop, I pulled and cleaned all spark plugs. All were coated with thick carbon deposits. I also rotated a valve (attached to distributor with 4" long black plastic arm) that sits just behind the electrical distribution assembly. Apparently, this opens up the valve to allow carbon burn off. I found this additional suggestion during my search for answers.
I then pulled fuel pump fuse, floored gas and cranked engine. After 4th - 45 second turnover sequence it sputtered for about 15 seconds and finally started. Replaced fuse and much smoke followed after starting. Smoky exhaust cleared after a couple minutes and ran at 2500 rpm for 20 min. It is running fine.
Thanks for the help, you certainly earned your fee!