engine shaking/pulsating - need help with diagnosis
#1
engine shaking/pulsating - need help with diagnosis
Hi guys, originally had this problem over a month ago when I was in another state back in college....It only happens when I'm idling in drive or reverse but it's like engine shakes/pulsates every so often. I first thought it was jut the car being old and the transmission being whiny or something. Fast forward a month later to now....I've driven 650 miles to another state for my summer internship and been driving over 200 miles a week. It was last week and primarily yesterday when this pulsating/movement of the engine got really noticeable. An hour later, the SEL came on. Gonna take it into autozone today to get the code checked for free, bu I was wondering beforehand if anyone here had any ideas n what s causing this shaking. I red a lt f old threads, and it doesn't look like a misfire because I haven't noticed a drop in performance while driving (none that I've noticed anyway) and the fuel efficiency hasn't changed either as far as I can tell. So anyone got any clues?
#4
word man i feel you on that i have the same problem as well it shakes on idle and sometimes reverse it goes and leaves from time to time not sure what it is i changed spark plugs thinking that was the problem but it wasint i havint changed coiles yet but would really want to fix this just as much he does so please any info would be good for us
#7
My 1995 Maxima engine started running really rough, my mechanic diagnosed a bad injector #6, replaced it and now it is smooth *most of the times*. But now I have the same exact symptom as tarun900 = engine shakes / pulsates intermittently while idle in drive or reverse, runs just fine on neutral or park. Does not happen while cruising, at least I can't feel it happens then. No engine check light yet, my mechanic saw no code in the ECU either, suggested I keep driving it until a code shows up. Can it be the new injector needs a new coil as well? Does it sound like a coil problem and if so how does someone diagnose coil problems without engine codes?
#8
To find out which cylinder is having a problem, you have the engine idling and then unplug the wire harness connector from the coil packs one at a time. If the engine does not idle worse when you unplug the wire, then you have found which cylinder is having the problem. Now you have to determine if it is a coil or the fuel injector or a spark plug. You can swap the coil pack with another cylinder and then see if the problem follows the coil pack.
If the engine is running smoothly, then this will not show you anything.
If the engine is running smoothly, then this will not show you anything.
#11
#13
So today my check engine light came On and stayed On. I flashed the codes. 0302 and 0304 = both #2 and #4 cylinders misfire. Very strange. It feels like a misfire problem as the engine pulsates and shakes intermittently but runs OK otherwise. Still they only replaced injector #6. What else could have happened to bring about misfiring in 2 different cylinders?
Thread
Thread Starter
Forum
Replies
Last Post
James92SE
3rd Generation Maxima (1989-1994)
142
01-02-2024 09:23 AM