Engine knock at start-up
Engine knock at start-up
As a long time service center owner I have come across this problem on three car models.
The problem can be attributed to oil starvation at start-up. The first was Chevy”s early 2.8L V6. They had the oil filter mounted on the side of the engine. There was no check valve in the filter and when you stopped the engine the oil in the filter ran back into the pan. When you started you had to wait for the filter to fill before you got oil pressure. The fix was easy. Just changed to oil filter to one with a check valve. The second was a New Ford Contour SVT with a high output 3.0L V6. I told the dealer that if he could show me another similar car with the same knock I would let him off the hook. I ate the car. I also never found a fix. Now I have purchased a 99 Stratus, 2.5L V6, with 62KM. Same problem. When cold starting the engine starts at 1500RPM and drops to 1000RPM. That instance of 1500RPm is enough to momentarily cause an engine (sounds like a rod) knock. I have switched to 10W 40 Mobile One. It sure helps but not completely. The filter does have a check valve. I have played with the cold start electronics, but everything goes to a control module. Schematics show the control module as a box with connectors. Guess the circuitry is considered proprietary. I have pulled the plug on the ISC. It works for a few starts then really screws up the control module. Any thoughts???
The problem can be attributed to oil starvation at start-up. The first was Chevy”s early 2.8L V6. They had the oil filter mounted on the side of the engine. There was no check valve in the filter and when you stopped the engine the oil in the filter ran back into the pan. When you started you had to wait for the filter to fill before you got oil pressure. The fix was easy. Just changed to oil filter to one with a check valve. The second was a New Ford Contour SVT with a high output 3.0L V6. I told the dealer that if he could show me another similar car with the same knock I would let him off the hook. I ate the car. I also never found a fix. Now I have purchased a 99 Stratus, 2.5L V6, with 62KM. Same problem. When cold starting the engine starts at 1500RPM and drops to 1000RPM. That instance of 1500RPm is enough to momentarily cause an engine (sounds like a rod) knock. I have switched to 10W 40 Mobile One. It sure helps but not completely. The filter does have a check valve. I have played with the cold start electronics, but everything goes to a control module. Schematics show the control module as a box with connectors. Guess the circuitry is considered proprietary. I have pulled the plug on the ISC. It works for a few starts then really screws up the control module. Any thoughts???
