I am test the power supply to the map sensor. If i understand this correctly each of the two outside wires in the plastic terminal that the sensor plugs into should show 5 volts on the multimeter with koeo. One shows 5 volts. The otherlooks to be low at 3.6 volts. If I check ecm c19 for the,power supply at the ecm it test 5 volts.

With koeo c17at the ecm signal wire for the map is ok 2.9 volts. .94 with car running

Did i test the map pwer supply correctly ? How would you repair this. The wire harness is original and never given trouble. It looks ok.

What sort of problem would this cause for the crv ?

This all started due to a persistent ping under load acceleration on hills mostly when cold. On warmer days it almost goes away.

Otherwise it idles and runs smoooooth. Tune up, carbon cleaning and everything i know to do. Could this be the problem and how do i fix ?

Thanks!

 

Also i dont understand how this goes from 1 power supply wire at the ecm to 2 and a ground at the map. 1 is a signal wire. I did thhe test i found online nut 2 power supplies did not make sense

 

Firstly, the map sensor isn't your pinging problem.

One wire is 5v+ another is ground and the 3rd is the signal back to the ecu.

I'd start with checking the base ignition timing.

 

Thanks, i sort of thought the same thing on the map wires. 1 ground, one signal and 1 power.

There was a test for the map posted on here that looked to be copied from the shop manual that said the 2 outside wires at the terminal should each have 5 v.

One of my wires has 5, one is ground, and one is 3.6. I dont understand why it would have3.6 from the ecm. How much is it supposed to have ? If its signal and not hooked to the sensor why would it get 3.6 from the ecm ?

 

I'm not sure how you are getting 3.6v on the signal wire with no sensor. But, 3.6v is roughly atmospheric pressure as the map sensor reads.

 

Anyone else have ideas about why one of the wires would show 3.6 v from the ecu ? I have 5 v, ground, and 3.6 on the 3 wires from the ecu going to the map sensor.

Thanks