So my 1999 Sentra SE(SR20DE), seemed to start pulsing at low RPMs during and after i replaced a bad O2 and knock sensor.(which retards the timing)
parts replaced:
plugs
wires
dist cap and rotor
fuel filter
Possible problems:
egr???
Also I used all oem parts. Any input is helpful
MAF/MAP sensor issue? Not really sure which your car has I’m assuming it’s MAF.
Check/clean the connector make sure it’s not corroded, not sure exactly what you would need to do to test it on your car.
reset computer?
If it is misfiring then a MIL should appear on the dash. Does it? If so what is the code?
What were the codes orignially for when you replaced the 2 sensors?
Sounded like a MAF problem to me at first but without more info its hard to say.
I got P0325 and P0138 a while back, after replacing them i reset it by just disconnecting the battery for a day, and the light went off. Are there any kind of soft codes and how would they be checked?
I will check the MAF connector in a bit
p.s. the car has 122k on it
check maf as stated above…but a shit idle and low end until revved I have seen numerous times to be the timing belt jumped or was set wrong. Put the car on jack stands, put piston 1 to TDC and make sure all your Cam timing marks are PERFECT. One tooth off on the cam can commonly cause what you are experiencing.
me too. Maybe it could be a faulty sensor. Try replacing the new knock and o2 sensor with the old ones and see if it changes. I would def try checking the timing too. I find it wierd its not throwing any cells tho…
Car idles nicely.
Just as you pull though the rpms you can feel the car pulse.
Not hard but enough were you feel a wiggle if that makes any sense.
What did you set your timing to?
A bad MAF would = not being able to rev past 3000 RPM at all.
What belt?
So let’s replace parts A, B, C, and D. And then when it changes performance from before start checking parts E, F, and G since absolutely nothing could have gone wrong when installing A, B, C, and D.
yea i was just gonna say that motor is a timing chain
Yep.
Car had a CEL for a bad 02 and knock sensor.
A retarded monkey with a wrench could fix those. I doubt anything went wrong even if that knock sensor is a complete bastard to get to.
The car was running worse prior to changing those parts.
But this pulsing issue has been ever present.
Also wires and dizzy were the original so it was under the maintenance list of items.
Timing has not been set and should be.
Better yet, What should it be set to?
As long as that monkey has a double jointed elbow then yes.
IIRC 12-13* is at the low end, I run 15*, nice and safe on 87 oct, 17* is the upper end.
http://www.sr20forum.com/technical-information-library/225999-how-adjusting-ignition-timing.html
19* if you want to run 91~93.
yes, it is a timing chain, and i did not mind doing maintenance that should of been done anyways. It only really occurs only during 2.5 to 3.5 k ish area, anything lower(idling) or higher feels fine.
update: contacts on maf connector look fine, also tried running 91 and no real change so maybe the timing is lower
Does this car have an EGR?
update: checked timing and it was spot on, 15*, checked for bad ground on maf, fine as is.
under light-moderate acceleration it will misfire above 4k, if you give it more gas it is just not as noticeable.
maybe distributor itself or even something with the fuel delivery?
After this mess I will never again assume that the problem has to be related to something I just changed.