Engine hestitates/misfires on hard acceleration
#1
Super Member
Thread Starter
Engine hestitates/misfires on hard acceleration
This 97 has the 104 engine. When I try to accelerate into merging traffic for example it suddenly starts to hestiate, sputter, misfire and carry on.....if I back off the gas it takes a second or two to "clear it's throat then if I am gentle it will accelerate upto speed.....but only with a nice gradual acdeleration that doesn't require the transmission to down shift. Come to think about it has always has this weird hesitation when I have it downshift at high speeds, like passing on the highway. Never did it when moving off from a start. Until to-day. Any ideas? Getting a pending P0460 code. Has always had a P0170 that I spent time trying to clear a couple of years ago and gave up. Pain in the butt.
#2
MBWorld Fanatic!
Clean
the mass air sensor or replace it.Driving around with a fuel trim code for this long may be from a bad o2 sensor and since they are 100k mile maint items it is time anyway
http://www.autohausaz.com/search/pro...xygen%20Sensor
p0460 fuel level sensor.Not active it may clear itself.
Bad o2 sensor,faulty failed out of range maf,ruined cat converter from the ignored p0170 obd2 code,can all cause the hesitation on acceleration you are suffering.
ohlord
check all the wires for rat damage.they love those m104's
http://www.autohausaz.com/search/pro...xygen%20Sensor
p0460 fuel level sensor.Not active it may clear itself.
Bad o2 sensor,faulty failed out of range maf,ruined cat converter from the ignored p0170 obd2 code,can all cause the hesitation on acceleration you are suffering.
ohlord
check all the wires for rat damage.they love those m104's
#3
Super Member
Thread Starter
When the P0170 code first started I diligently cleaned and re-cleaned then replaced the MAF to no avail. In fact, it even passed an emissions test when it was on. Go figure. The cat is OK 'cause the car is fine at high RPM....once we get there. No code for the 02...so it is probably OK too. Probably a fuel supply issue or vacuum.....to-days task is to mix. Tomorrows task is to dump it. Worst car they ever made. And that is saying something when you look at their recent offerings.