View Full Version : RPM Needle drops while accelerating
dhquinn40
Nov 2, 2010, 10:03 AM
It's mainly when the engines cold. So in the morning and after work. You would accelerate like a normal person and somewhere in 2nd or 3rd gear the RPM needle will drop even though you still have your foot on the gas. I had cylinder 3 valve issues not long ago and paid a ton to get them fixed on to have the same issue return. I keep thinking somehow it's running lean and that's how it contiues to burn up valves. I've heard TPS MAF MAP vacuum leaks and numerous others but I can't figure this one out for the life of me and have run out of money to fix it. Please help if you can.
Thanks
CaptainRich
Nov 2, 2010, 11:13 AM
https://www.askmehelpdesk.com/cars-trucks/when-asking-about-your-vehicle-303903.html
TxGreaseMonkey
Nov 2, 2010, 11:29 AM
If your car is a Honda, the tach problem may be related to a failing Ignition Control Module (ICM). The BLU wire from the ICM goes directly to the tach. Erratic tach rpm is frequently a sign the ICM is bad.
Burned valves are often due to adjusting the exhaust valves too tight. It's better to have them a little loose than too tight.
dhquinn40
Nov 2, 2010, 01:06 PM
Yes it is a 2000 Honda Civic EX (D16Y8) I will research the ICM issue. I keep hearing change the TPS only with the other ignition parts... Dist/Rotor plugs and wires. It has also been said it could be an vacuum leak. This is driving me up the wall. I can't figure this one out.
TxGreaseMonkey
Nov 2, 2010, 01:14 PM
TPSs almost never fail. A vacuum leak is a possibility. If you have a 120,000 miles or more on your Civic, you really should replace the ICM anyhow. Here's how to do it yourself:
https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-hondas-selected-other-vehicles-46563-4.html#post265896
dhquinn40
Nov 3, 2010, 04:51 AM
What would be the best way to check for the vacuum leaks? Should I get carb spray and slowly check for leaks that way? I have read other forums that have somewhat of a similar problem and nothing gives a definitive answer on the culprit. It seems as though it can be a wide range of issues. I talked to Honda about get a full diagnostic but I know they will find a way to keep if for hours and hours at a rate of 80 to 90 per hour. That's ridiculous but I may have to take that route before cylinder 3 is completely shot again. Any other ideas?