HI all new to the site but not to hondas. Recently got my b17a1 running in my 91 civic hatchback. It ran pristine in my old crx and i broke the knock sensor. It put the cel on but still engaged vtec just fine. I had serious wiring issues when i swapped it to the civic cuz the previous owner wasnt that smart. In any case it now runs fine figured out all my wiring issues but now vtec doesnt seem to engage at all. It revs fine havent taken it to the limiter yet becasue im afraid of hurting it.It seems to rev fine well beyond 5500 rpm where vtec should engage. Motor is stock except for an old school nuespeed header and an aem intake. Ive checked and rechecked all the vtec wiring and its good with the exception of the knock sensor not being hooked up Also checked all my grounds the vtec solenoid seems to operate just fine and im really stumped. Any suggestions?

 

hmm man seems like u didnt change ne thing...this may sound silly but start with the easy stuff... coolant and oil levels...etc stuff like that..

 

Coolant level is good made sure i let the car warm up to proper operating temp cuz i know it wont engage other wise. Oil is also good. It seemed a little thin since it sat for so long and ive been thinking maybe that was the problem. Changed the oil today and still no go. I read somewhere yesterday that if it doesnt see rpm it wont know what rpm to engage and the car has the stock cluster in it. I tried swapping it to my 89 si one but one plug is different and i cant seem to find a writeup about which wires need to be swapped on the 89 cluster to make it work. But that still doesnt make sense since the ecu should read rpm from the kdizzy right? Trying to get ahold of a 91 cluster so i dont have to do any more wire swapping

 

Well I had the bright idea to take a piece of wire form the solenoid side of the gray pin connector run it in the since the battery has been relocated and put it to the pos side of the battery, which made the solenoid click like it should so i deff know that the solenoid is good. My question is now what pins ground vtec? It wont hit when connected to the connector which itself has been hard wired to the ecu from who ever did the swap in the crx i used to own.

 

are you throwing any codes.... i dont think vtec will kick in if you have one. You said that your knock sensor was broken hit up the junk yard thats where I would start.

 

Vtec should engage even without the knock sensor. Just retards the timing some. Which is weird cuz like I sated it was fine before in the crx with no knock. Its next to impossible to find one in a junk yard around here cuz you will never find a bseries motor that isnt an ls. Ppl around here got the inside tip. something nice comes in and its gone before it even hits the yard. Anyone know what if any d-series sensors would work? Also I cant check the codes cuz there is no blinking lights or any thing Id be almost positive the cel is for the knock sensor. None of this makes sense at all to me why its doing this. Someone told me to put it on a window switch but I absolutely refuse to do this. Any one know if Not having a tach would make it not hit? I still have the standard gauge cluster in it as the one I have is for a 89 si.

 

Has VTEC ever worked in the new chassis? You need to check the codes... There is a pin on the ecu that needs to be grounded and it will flash your CEL. (Assuming you have it wired OBD1) Not knowing the codes is going to make trouble shooting almost impossible.

 

It would be like a A13 right?

 

Oi have a buddy with the same engine in a crx and he vtec wont engage after he broke his vss cable there is a signal from the speedo to the ecu and if the ecu is not chipped to ignore the vss speed check before engaging vtec it will not work check to make sure you have a signal wire from the cluster to the ecu. and its not broken or shorting out. there is something in teh cluster the converts it from cable to electric. Hope that helps.

 

The vss should be fine. CLuster is also good as far as i know. Ive been having a problem figuring out exactly how to check the codes on the car as I dont have comp access where I live . I also think my problem maybe A wire that i found that somehow became disconnected from the subharness. All I need to do is find a Wiring diagram that shows exactly what pins are used for vtec itself. Once I do I should be golden. Just dont have much free time or money to travel back and forth since the car is where I have comp access. Thanks for all the replies fella's.

 

these should help with your harness

 

Thanks but the bottom half I cant read whatsoever its just to terribly small. Can you pm a link to where you found this? Thanks a ton for the info.

 

I cant remember where I found it ... just save the pic to your hard drive and zoom in

 

Checked the codes. One blink then 6 flashes, then 7 flashes than 9 . Any ideas ? Im sure this has been covered but i cant seem to find a guide to the codes and what they mean. Thanks again.

 

https://honda-tech.com/forums/honda-crx-ef-civic-1988-1991-3/all-ecu-codes-you-will-ever-need-1710584/

in the faq