speedometer off when sr20 installed

[hieu2ueih]

hi just bought an s13 sr20det blacktop and for some reason when the guy installed the sr in he said the speedometer only reads half of your actual speed. can anyone guess as to why this is a problem? its a 91 240sx hatchback

[Hijacker]

That makes no sense to me. The speed sensor for the S13, whether SR or KA, should read the same. Try to see if your guy can install your old speed sensor (assuming you had a manual car to begin with) and see if the problem still exists.

[hieu2ueih]

no the car was not a manual. it was bought with motor/transmission and put in.

[Hijacker]

I have a sneaky suspicion your guy re-used the KA auto speed sensor then. Ask him what sensor he used.

[hieu2ueih]

so i just need to go get a s13 manual speed sensor then?

[Hijacker]

Ask your installer first what sensor he used. If he used your auto sensor and still has the manual sensor, it would be quick and easy to just swap them out. If you do need to source one, I would just try to source one from a junk yard.

Go to Car-Part.com to find some good yards near you. I use Church's and Speedy's a lot. Both are located in the Greensboro area IIRC. Also, Tri-City Salvage is a good yard as well. They're located between Winston-Salem and Greensboro.

[hieu2ueih]

he said he used the one that came with the sr20

[Hijacker]

That's odd. You've driven the car and verified that it's reading wrong?

If so, just replace it with a USDM sensor off a KA. They're cheaper and easier to get a hold of.

[hieu2ueih]

yeap bought it yesterday and drove it home. it read 30 when i was going 65.