Rough Idle

[Dao]

I have a 2001 Acura Integra GS sedan, automatic transmission with 167,000 miles. It’s never had any serious repairs and it’s had no major maintenance before. On Oct 3 while driving home engine suddenly quit while I was making a right turn. The car coasted to a stop on the road, I tried starting it but it sounded like the motor was spinning a lot faster than normal but no start. Towed it to our house that night. I assumed that the timing belt snapped. The next morning I take off the valve cover and see that some teeth are missing on the timing belt but it did not snap. I was scared that the valves may have bent. I decided to slap a new belt on there and see if it starts because I have all the new parts to replace it anyways. So we replaced water pump and timing belt. Got it timed. Then the vehicle started! Which is great but it has a rough idle. The engine shakes a lot when idling. When we rev the engine, it is smooth and sounds normal with no shakes.

Things to note are that we have yet to air out the coolant system, which is the next thing we are going to do.
Some things running through our minds as to what could be causing it is:
– Air in the coolant
– Timing is off

A random question I have is: Would doing Ignition Timing benefit the rough idle at all? Like using the timing light.

Thanks for the help!

Topic

[IM]

I would do a leak down test to check for the valves. your engine B18B1 is an interference type and would probably have bent the valves causing the rough idle you’re talking about.

[Dao]

[quote=”stilkus” post=148613]I would do a leak down test to check for the valves. your engine B18B1 is an interference type and would probably have bent the valves causing the rough idle you’re talking about.[/quote]

Thanks Stilkus, my friend and I will be doing a leakdown test on Thursday 10/8/15 and I’ll be updating this thread.

[IM]

hopefully it’s only a valve or two which you could adjust with the tip of a screwdriver.

[Dao]

Thank you so much Stilkus for the suggestion again. So we got the valve cover off so we could see the cam gears so we knew for sure which piston was in top dead center for the leakdown test. We turned the crank to get the 1 piston into TDC and it looked off by a tooth for the intake cam shaft but we ran the leak down test. We did it for each piston, and we did run into leaks and it did seem like valves may have been bent. But after we did that we decided that timing was off and we re-adjusted the timing and it looks SPOT on this time. We ran the leak down test again, and everything was very good and was within spec’s for the leakdown test. We got everything back together and after waiting for the gasket sealer to dry we started up the car and it runs perfect.

I was lucky that the internals didn’t get banged up or enough to where the car wouldn’t run well. Super happy and grateful. 🙂 🙂 🙂

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