havent actually installed it yet, i just had a question. it is supposed to have like 500 ohms of resistance, right? well checking the new one right out of the box, should it have that? it is wide open on one pin, and there is continuity on the other. you know, like zero on an ohmmeter. anyone know?

 

not shure what resistance its supposed to be but set your multimeter in ohms and when you put the meter to each of the leads it should show you what resistance it is.

 

They have a MUCH higher resistance than that. Mine measured 0.550 MEGA Ohms, which is 550,000 ohms.

The old one had a similar resistance, but was obviously bad.... since the installation of the new one GREATLY improved power output. According to the Haynes manual, they provide an AC output, which will change with engine knock... so they are tough to diagnose in a 'static' state.

Without a reader that can measure its output while the car is in operation, diagnosing a bad knock sensor is pretty much a 'crap shoot'.

Mine threw NO codes and still measured around the right resistance, but was still bad. Go Figure...

Also be sure to check the condition of the wiring leading to the KS. Check for continuity with a meter (to make sure the wires are connecting) to be sure there's no problem there.

Here's the rundown of my install from a previous post...

I just replaced mine... and D*MN, what a difference!

The fuel mileage had suddenly fell off a few mpg, and the power was feeling a little soggy.... Plus, there was a little hesitation just over 2k rpm.

Now, the part throttle low end and midrange feels like a totally different car! I can't believe the difference. It runs WAY better all the way across the rpm range!

One trick I've heard is to mount the knock sensor to the firewall, where it won't feel any 'knock' and will never retard any timing. This would work great as long as premium fuel is used..... and is what I would probably do if I raced this car a lot.

Just a thought.

Oh, I purchased mine on ebay for $90 'buy it now' and $1 shipping.

It was removed/installed with a 1/4" drive 12mm socket and a good swivel.... and a long extension. My wife's small hands came in handy with the initial installation of the new unit. I then tightened it down.

BTW, my car's check engine light was not on, and it showed no codes. The fuel mileage and power just fell off.... and it had a bit of a hesitation, which led me to believe it was bad. If your car suffers from these symptoms, GET A NEW KNOCK SENSOR!

Good Luck!

 

does anyone know the symptoms of a bad IAC-V? i already replaced my MAF and KNOCK sensors. and my car is having major acceleration loss. when i get on the gas sometimes i cant get it to pass 5k rpm's, and sometimes the car hesitates and the rpm's drop during hard acceleration. the ecu is throwing out a IAC-V and oxygen sensor code only but it was also throwing out MAF and Knock sensor codes as well. what is causing my power loss.

 

i would suggest changing the knock sensor and iac and resetting the computer thereafter. I just went through this ritual once my check engine light went on. now it drives like new again. amazing.

 

If the KS is very sensitive, it may send false knock signals to the ECU. The result is a weak engine, but there is no error code. This problem is very hard to diagnose. If you suspect the KS is sending false signals, you may want to put in a 550K resistor and see if the engine gives more power. This is for testing purpose only, and make sure to use premium gas. If you hear any knock, stop asap or engine may be damaged. An alternative is to simply unplug the KS and see if the engine gets any weaker. If no change, then the KS is probably not doing its job right.

When replacing KS do not overtorque or it may become too sentitive.

 

Thanks,So its a KS prob. than?? I already replaced it with a new one. i still

havent changed the iac. can a bad iac cause acceleration loss? i heard that if it is not working right that it can affect the aif/fuel ratio in return causing hp loss.

 

just clean your iac unless it is a faulty electrical problem. there is a write-up on this in the how to's here in the 4th gen forum.

 

If the ECU has other codes in addition to the KS code, fix the other problems first. Don't forget to clear the ECU. Sometimes the KS code is due to the other problems.

 

all that and it was just a stupid IAT sensor. replaced the IAT and my care went from running 15.7 to a 15.1 wow!!! it finally accelerates like it used too.