WHAT TO DO TO FIX COLD MISFIRE.
2004 Cadillac Deville • 78,000 miles
After sitting for the last month, the engine misfires at cold startup. Misfire evens when put under a load. No hydrocarbons detectible in the coolant. Misfire more severe as weather gets colder. Dealer mechanic pulled one or two plugs which appear to to be fine. Dealer mechanic says the rough cold idle is "normal" but I have driven the car since new and know better. Too, I have rented a number of these cars, including newer, and found that none of them start up with a rough idle. I wonder about fuel air mixture, which would point to the throttle body or the secondary air pump. Are there sensers there that could cause this condition? Other?
November 9, 2011.
November 9, 2011.
It could be a vacuum leak, the plugs may need replaced even if the couple he pulled look good. If a check engine light has come on, have the computer scanned to identify where the trouble is coming from. And, no, it isn't normal.
The dealer mechanic states that a check for vacuum leaks was done and there were no leaks.
No, the check engine light has not come on. The mechanic said that an instant read of codes indicated that the car was sending a code (I don't know what that was) but that it was not strong enough to register. Is it possible that one of the in-bank oxygen sensers could cause the secondary air pump to lean out the air-fuel mixture sufficiently to cause this condition? If not, then it seems that the only logical problem is bad spark plugs?
An O2 sensor can cause a lean mixture. Also, a temp sensor can do the same.
1986 Nissan Stanza, California version. The engine wants to die when stopping. I thought that the lock-up switch for the torque converter was not unlocking. I have installed a used ...
2 answers • 1986 Nissan Sunny • 100,000 miles
1999 Hyundai Elantra mileage: 110,000. This car idles fairly well in neutral or park but very rough in reverse and drive. I just replaced the engine with a used engine and it is doing ...
1 answer • 1999 Hyundai Elantra • 110,000 miles
1988 Chevrolet Astro Van mileage: 247,000. It's time to replace the engine in my 1988 Astro. I bought a 4.3 V6 that has come out of a 1991 S-10. When I dismantled it to get it ready to ...
1 answer • 1988 Chevrolet Astro • 247,000 miles
1990 Toyota Camry mileage: 150,000. 1. The oil warning light is on. 2. There are four quarts of oil in the car. 3. The oil filter is dry. 4. The engine sounds rough. 5. There is noise ...
3 answers • 1990 Toyota Camry • 150,000 miles