Bad idle & 300s codes
#1
08-16-2012, 04:50 PM
Bad idle & 300s codes
The truth will set you free!!! I have been trying for over six months to solve the usual and infamous bad idle problem. On a number of occassions, I have proclaimed to have resolved the problem only to later sink into dispair when the lopey idle and pesky codes returned.
Yesterday, I finally capitualted and brought it into another shop. The mechanic said I indeed, had done everything possible to solve the problen and it was over his head too. I had adjusted valves, cleaned the plenum passage, new wires, plugs, cap, bled cooling system and everything else. He did say there was a lot of blowby out the dipstick. I ran the car with oil filler cap off and it smoked like a mosquito fogger. On new cars you dont often see blowby because it goes right into the intake. I ran a compression test and found the middle cylinder on the front bank consitently pumped just 60 lbs while the adjacents pumped at least 160.
As a "Hail Mary". I ran Seafoam trough the crankcase and changed the oil. Plus overnight, I did a Seafoam soak of the deficient cylinder and the compression rose to about 80lb. I am currently running a quart of ATF as a cleanser hoping it will desludge a gummed up ring?
The mechanic also heard a "knock" that I have heard so long I just ignored. I am lookong for a new engine. Can you pull it from top? Anyone know?
These engines can run a long time with bad cylinders; this one is still working and has been running like this for a year now although it sometimes stalls at idle especially with the a/c on.My advice to all you folks out there with the idle problem is do a compression test before you waste a lot of time and $$ on valve adjsutments, plenum cleanings, throttles bodies, distributors and egr valves etc. Dont assume that just because it's a Honda that it'll run forever. A classic symptom of multiple misfires, poor idling and stalling is bad compression.
Bad to hear but at long last good to know why. My advice is to anyone with an idling problem is to first do a compression test before you waste time and money on things that wont help.
Yesterday, I finally capitualted and brought it into another shop. The mechanic said I indeed, had done everything possible to solve the problen and it was over his head too. I had adjusted valves, cleaned the plenum passage, new wires, plugs, cap, bled cooling system and everything else. He did say there was a lot of blowby out the dipstick. I ran the car with oil filler cap off and it smoked like a mosquito fogger. On new cars you dont often see blowby because it goes right into the intake. I ran a compression test and found the middle cylinder on the front bank consitently pumped just 60 lbs while the adjacents pumped at least 160.
As a "Hail Mary". I ran Seafoam trough the crankcase and changed the oil. Plus overnight, I did a Seafoam soak of the deficient cylinder and the compression rose to about 80lb. I am currently running a quart of ATF as a cleanser hoping it will desludge a gummed up ring?
The mechanic also heard a "knock" that I have heard so long I just ignored. I am lookong for a new engine. Can you pull it from top? Anyone know?
These engines can run a long time with bad cylinders; this one is still working and has been running like this for a year now although it sometimes stalls at idle especially with the a/c on.My advice to all you folks out there with the idle problem is do a compression test before you waste a lot of time and $$ on valve adjsutments, plenum cleanings, throttles bodies, distributors and egr valves etc. Dont assume that just because it's a Honda that it'll run forever. A classic symptom of multiple misfires, poor idling and stalling is bad compression.
Bad to hear but at long last good to know why. My advice is to anyone with an idling problem is to first do a compression test before you waste time and money on things that wont help.
#2
08-16-2012, 08:42 PM
Pulling from the top is possible based on recent post asking this question. A search should find the post. It was w/i the last 2-3 wks.
good luck
good luck
Thread
Thread Starter
Forum
Replies
Last Post
Mysticalbeauty3
General Tech Help
2
10-06-2008 04:17 PM