weird one here. just put in this jdm engine. knock sensor looks to be cracked so that could be part of the cel. really weird part is this engine stumbles the second you crack the TB, almost like the timing isn't advancing or the injectors aren't keeping up

longblock checks. compression is great and it has 23" of vacuum. so little blow by that even with the oil cap off there is no pulse on your hand.

sensor related, ideas? wish i had a usdm ecu to pull codes. it's a hard failure whatever it is. with the key on when the cel cycles it stays on. almost reminds me of something distributor related, like the timing isn't advancing

http://www.youtube.com/watch?v=iCD2K...ature=youtu.be
http://www.youtube.com/watch?v=gx_zz...ature=youtu.be

 

What year make and model?

I used the same method for obd1 cars on my 97 GSR when it was running the obd2a p72 ecu. Worked the same. Doesn't hurt to try.

 

have ecu p73-003 in a 97 gsr. get code 61 and 14 which make no sense unless i have the iacv and knock plugs switched? need to check that tomorrow

 

61 and 14. primary o2 sensor and iac.
check to see if the o2 sensor is switching. the o2 code will trigger the iac

 

wild, what's a good process to do this? normally on obd2 i can use the scan tool and find out. since jdm operates like obd1 how would one test it?

may not make a difference besides knowing since i have another known good o2 i can plug in and test it with.

that stumble is what had me going wtf?

car does not idle at 1200 cold, it at first wouldn't idle at all, then with a little help and messing with the TB screw it idles at 800 warm or cold.

compression is 255 in each cylinder warm and it has damn near 24" of vacuum. so my internal health is good, this is just an issue i have never encountered before.

i swear i had a code 15 at one point but it didn't show up again. could have been a miscount but.....?

the bottom vid really shows what i'm talking about. i'm holding the tb steady when you hear it surge

 

when you adjusted idle, you followed the procedure?
although, idle shouldn't be adjustable with those codes. usually the pcm won't allow it. you probably had a hrd time adjusting it, yes?
to check the o2 sensor, with the vehicle at operating temp, back probe the o2 signal wire. it should switch from .1v to 1v on and off. i think the signal wire is usually the white one.
you can try another one, but of course, if it's a problem with the circuit, or pcm, it won't make a difference.

 

idle wasn't adjustable what so ever. all opening the screw did is take it from not being able to start without having my foot slightly on the gas to it actually starting and the idle being locked. the CEL comes on regardless of if the car is running or not. when the key goes on and it cycles through it flashes off then comes right back on before start.

i'll backprobe the o2 tomorrow and see if it's functioning correctly. do you remember or have access to the wire colors for the knock sensor and iacv?

i have a couple plugs i honestly forgot where they go.

1. green plug by vtec solenoid..not used with jdm vtec solenoid, check
2. cfs sensor plug, not used with jdm ecu, check
3. a green and grey plug on the back of the block. green plug looks like the vtec oil and green typically is oil. only have a knock sensor on this block. ahh... need to run up to english racing tomorrow and look at my old engine

 

A bad IACV will cause the car to stutter or stall. Check and make sure you didn't mis plug your knock sensor and IACV.

 

you know the idle control valve colors for obd2a?

i'm gonna paw through the haynes in a minutes. i need to double check all my connectors. been a few years since i did a swap, forgot they all use the same damn plug

have the oddest feeling my iacv and iat may be crossed

 

since it's a hard fault, chances are the plugs are mixed up, or sthg not plugged in
i've got the same crappy haynes manual at home. alldata and mitchell at work. you'll probably have it figured by that time

 

fixed it. same suspicion on a hard fault being switched plugs. switched the iat and iacv, hard fault went away, car fired, went to 2k for a second, dropped to 1500 and idled perfectly in warm up mode. throttle is responsive and the car appears to run perfect.

i used flex wrap around the extended iacv wire, when it was in the iat plug i was like....man i don't remember seeing this here. you know, how you have kind of a mental picture of your engine. looked on the computer and found a shot of my old engine and sure enough, the iat did not have that wrap. switched it with the only logical choice and all is well

except i broke the knock sensor unplugging it. literally pulled it in half when i unplugged it...not a huge deal i suppose if it was that weak it was a dead sensor walking