Knock Sensor Or not

[kellychud]

Hi this is my first post

I have had my 1990 Q 45 in the shop for over 1 year on and off it has new computer maf spark plugs and anything else that could be changed. The car starts runs but is sluggish and no power until 40 mph. I have read posts describing knock sensor info and the mechanic did the tests but they work we just dont know if they work properly and broke

[elwesso]

check your fuel pump

[Q451990]

The ECU stores knock sensor codes for quite a few start-up self tests... If your technician has access to Nissan's Consult he can look at the stored codes. Or you can check the ECU codes yourself by adjusting the set screw on the ECU.

Chances are good that if they ohm correctly, they're OK. I don't think bad knock sensors would cause a severe driveability issue anyhow. I found it to be a "something just doesn't feel right" issue.

I agree with Wes - check your fuel pressure and volume.

Heath

[paranoidjack]

Chances are good that if they ohm correctly, they're OK. I don't think bad knock sensors would cause a severe driveability issue anyhow. I found it to be a "something just doesn't feel right" issue.

Heath

Heath, I agree with you 100% that if they ohm within spec, they will be fine. I can say that from personal experience with my Q.

However, driveability!? You must have had some KS failures that were not very extreme, I've had some KS failures that were so bad I deemed the car undriveable. Got rid of my J30 because I didn't feel like dealing with it and it was so hard to drive. With the (slightly) torquier vh41 it didn't feel as bad, but still I found it to destroy the car's driving up until 3750rpm.