S300 idle too low.

delsolitude · Post by **delsolitude** » Tue Nov 28, 2006 4:35 pm

i just put an obd1 p72 ecu in my B18c delsol
originally it was obd2 p72

the old ecu works fine... idles high at start.. but drops...

the new ecu flags error IAC and error 20 electrical load (not important?)
the idles fine when u start (not as high as the old ecu) but it slowly drops till it drags around 500 then stalls(jumping up and down in the process)

when datalogging the lambda shows 0.0 at all times... is there a good link to know what lambda is? i search around but all i get is greek alphabet junk.... is a stock p72 map supposed to be lambda 0.0? if so then it isnt a problem.

the s300 apears to upload and download fine. datalogs fine too.... so i assume my install job was sufficient... if it does that its 100% installed?

could the iac error be a soldar error?

any help would be greatly apreciated. thank you...

Post by **Spunkster** » Tue Nov 28, 2006 6:19 pm

Do you have a wideband? Has the car been tuned on the dyno?

delsolitude · Post by **delsolitude** » Tue Nov 28, 2006 6:24 pm

Spunkster wrote:Do you have a wideband? Has the car been tuned on the dyno?

the car hasnt left my driveway with the new ecu

nothing tuned on the dyno.

and im new to most terminology.
do i have a wideband? i assume since i dont know... it means i dont...
sorry for the daftness :?

would a totally stock B18c car (integra) have a wideband?
and would a totally stock b18c read a lambda of 0.0 in hondatas300?

Post by **Spunkster** » Wed Nov 29, 2006 10:23 am

You don't have a wideband, so you will not get any lambda readings. IF you are unsure of what you are doing, I would suggest you start reading the Help file by goign to Help, Contents. YOu may also want to consider taking the car to Hondata dealer to have properly tuned, or you may damage your engine.

delsolitude · Post by **delsolitude** » Wed Nov 29, 2006 2:17 pm

Spunkster wrote:You don't have a wideband, so you will not get any lambda readings. IF you are unsure of what you are doing, I would suggest you start reading the Help file by goign to Help, Contents. YOu may also want to consider taking the car to Hondata dealer to have properly tuned, or you may damage your engine.

oh dont worry im not tuning it myself... i just happen to know how to do soldaring myself so i installed it myself... just making sure the 0.0 isnt a soldar problem. thank you for your help. so i guess its just i IAC error... wich from what i understand isnt a big deal

thank you for your help.

one last quick question wich is iac related.
with a stock obd2 p72 can a obd2 scanner disable IAC error?
i notice with hondatas300 u can disable it.....

trying to understand why my obd1 ecu is flagging an error but the obd2 ecu isnt(as far as i know). i dont have an obd scanner so i dunno... and the people who did the swap obviously wouldnt tell me they fucked up and bypassed cuz they are lazy

or is defective ecu the only possibility?

Jaker · Post by **Jaker** » Mon Dec 04, 2006 1:40 pm

Do a bit of research on the world wide web about the wiring of the IAC and your wiring adapter. Its possible that your adapter has not accounted for the fact that there needs to be a connection from 2 different points on the OBD2 side to 1 location on the OBD1 side. The OBD2 cars had the IAC wired up at either A12 or A14, whereas the OBD1 cars all had them at the same place (A9 I think).

delsolitude · Post by **delsolitude** » Tue Dec 05, 2006 12:11 am

Jaker wrote:Do a bit of research on the world wide web about the wiring of the IAC and your wiring adapter. Its possible that your adapter has not accounted for the fact that there needs to be a connection from 2 different points on the OBD2 side to 1 location on the OBD1 side. The OBD2 cars had the IAC wired up at either A12 or A14, whereas the OBD1 cars all had them at the same place (A9 I think).

my adapter has both a12 and a14 wired together. the idle air control valve gets 13.8 ish volts when the cars on
and 11.8 when its off... seems to follow the same pattern as the rest of the cars voltage? doesnt make sense....

the stock ecu (obd2) works fine and gets around 10.8v when the cars warm.

my sensor is the 2 wire. not the 3 wire.
ive run out of ideas...

anyone ever bypass the ecu and just run a set voltage to the iac?
wondering if i can get some sort of dial with an adjustable output.
im running out of ideas on this ecu. and no one i know with stock obd1 wants to co-operate and put a s300 in thier car.

Post by **Spunkster** » Tue Dec 05, 2006 10:58 am

You cannot wire voltage to the IAC. It is duty cycle controlled. Have you tried setting your idle per the Helms manual? There are also instructions posted in the forums if you search.