Car; 88 crx
motor; 94 b18b/95 intake manifold......
Well it wont hold idle, first thought was the IACV, replaced it, no luck, then My freinds told me that it may be the ignitor, replaced it, no luck. I checked for vacuum leaks, have not found any. all the sensors are wired corectly, i know because i yanked the sensor wire and then checked the code that it threw for each. I allso checked the intake manifold bolts to make sure that they were tight, they are. Any ideas? thanks in advance. I have failed the smog ref 3 times and its getting expensive, oh allso the smog guy said the numbers are really lean, and its failing the NOx levels. thanks


Rob

 

What injectors are you using? You need to use Saturated - OBD0 injectors ONLY... unless you wired to OBD-1...

 

its all obd-1

it used to run fine...


Rob

 

allso forgot to mention that it stumples at idle from time to time and sometimes stalls. But off of idle it runs good, other than the lean nuimbers. The lean numbers lead me to beleive that there is a vacuum leak somewhere, because it is getting more air and rendering the lean readings. HELP GUYS this is getting expensive


Rob

 

bump because if you dont help me im going to drive it off a cliff.

Rob

 

dude recheck your timing......... my car was doing the same exact thing and my timing was off by a tooth on the intake cam side..........

using a timing light it showed it was in time but when looking at both cam gears you could tell one was off.......... we lined up the gears once again and it ran perfect.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rjardy &raquo;</TD></TR><TR><TD CLASS="quote">allso forgot to mention that it stumples at idle from time to time and sometimes stalls. But off of idle it runs good</TD></TR></TABLE>

is your TPS vlotage in spec? check the voltage when fully closed to see if it falls between .45 and .5 volts. usually any less than .47V and i have trouble with a surging idle.

from http://www.hondata.com/techidle.html

The TPS tells the ECU what position the throttle is in. The TPS should read 0.45V when the throttle is released. It is critical that the TPS is adjusted correctly so that the ECU knows when the throttle is released, which tells the ECU that the engine is either idling, or the throttle is closed under load and the injectors should be switch off the save fuel (fuel over-run cutoff). Swapping ECUs that have different internal power supply characteristics can change the TPS voltage a small amount - in some cases enough to put it above 0,5V.

If the TPS is set negative (below 0.45V at idle) when you open the throttle slightly the ECU will think the throttle is not open, apply the fuel over-run routines and cut fuel at 1400 or 1800 rpm. This will often cause the revs to cycle between about 800 and 1800 rpm. Also the car will be jerky when driving around at low speed.

If the TPS is set positive (over 0.45V) then the fuel over-run routines won't work, and also the ECU will not run the correct idle routines to keep the idle steady. It's better to have the TPS adjusted slightly negative, but setting it to 0% if fairly easy with datalogging. Otherwise aim for 0.45V.

 

how will i know if the cam timing is off? Will it run allright past idle if the cam timing is off?

Rob

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by fastcrxsi90 &raquo;</TD></TR><TR><TD CLASS="quote">

is your TPS vlotage in spec? check the voltage when fully closed to see if it falls between .45 and .5 volts. usually any less than .47V and i have trouble with a surging idle.

from http://www.hondata.com/techidle.html

The TPS tells the ECU what position the throttle is in. The TPS should read 0.45V when the throttle is released. It is critical that the TPS is adjusted correctly so that the ECU knows when the throttle is released, which tells the ECU that the engine is either idling, or the throttle is closed under load and the injectors should be switch off the save fuel (fuel over-run cutoff). Swapping ECUs that have different internal power supply characteristics can change the TPS voltage a small amount - in some cases enough to put it above 0,5V.

If the TPS is set negative (below 0.45V at idle) when you open the throttle slightly the ECU will think the throttle is not open, apply the fuel over-run routines and cut fuel at 1400 or 1800 rpm. This will often cause the revs to cycle between about 800 and 1800 rpm. Also the car will be jerky when driving around at low speed.

If the TPS is set positive (over 0.45V) then the fuel over-run routines won't work, and also the ECU will not run the correct idle routines to keep the idle steady. It's better to have the TPS adjusted slightly negative, but setting it to 0% if fairly easy with datalogging. Otherwise aim for 0.45V.
</TD></TR></TABLE>

okay that sounds all correct but i dont have hondata, and i do know how i would just go about adjusting the voltage for the TPS. But what does sound correct is that it may be the tps, because when i unplugged the TPS plug, the surging corrected it self, but then of course it was not drivable at all, but it at least idled.

Rob

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rjardy &raquo;</TD></TR><TR><TD CLASS="quote">okay that sounds all correct but i dont have hondata, and i do know how i would just go about adjusting the voltage for the TPS. But what does sound correct is that it may be the tps, because when i unplugged the TPS plug, the surging corrected it self, but then of course it was not drivable at all, but it at least idled.</TD></TR></TABLE>

it has nothing to do with hondata...thats just where i got the info from.

get 2 paperclips or some thin wire of sort and shove it in the back of the TPS connector...i believe its the red wire and the green wire (which is + and which is - i cant remember). plug the TPS connector back in and hook your multimeter to the wires. turn the ignition on and check the voltage...move the throttle all the way open and measure that voltage too. you can also check it with the car idleing, just make sure your wires are out of the way. should be ~0.5V closed and 4.5V open.

if you need to adjust the TPS idle...you can do it with that little stop screw on the TB , it will just open or close the butterfly a little. or you can slide the TPS back and forth...but then you have to mess with those stupid torque to yield bolts. try and measure that...its worth a shot...and its free.

 

i recently swapt my engine in my 88 crx hf so maybe this will help. i just intalled a b18a1 and was having the the same problems. after doing all the trouble shooting that you have done i found that it was just a bad O2 sensor and when i checked my codes that the ecu was throwing they said nothing about a 02 sensor. go figure. but 4 migraines and a 2 busted nuckles later it runs great and you will love it when you get it running right. good luck, BRAD

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 88bottlefedcrx &raquo;</TD></TR><TR><TD CLASS="quote">i recently swapt my engine in my 88 crx hf so maybe this will help. i just intalled a b18a1 and was having the the same problems. after doing all the trouble shooting that you have done i found that it was just a bad O2 sensor and when i checked my codes that the ecu was throwing they said nothing about a 02 sensor. go figure. but 4 migraines and a 2 busted nuckles later it runs great and you will love it when you get it running right. good luck, BRAD </TD></TR></TABLE>


you know, the smog guy said the same thing, but its so new, but hell it could have gone out right? how much is a replacement? i didnt do the swap so i dont evan know what o2 sensor it is.

Rob

 

up

 

when my cam timing was off by a tooth, it would run fine past 1.5k rpms......... it would pull like a crazy cam after that............ i got a universal 02 sensor for bout 20 bucks......... could be diff for a b18 but i bought mine for a A6 si for my zc.

 

Hey rjardy, I'm curious as to where you are going to the smog ref. I'm in Sacramento and also have an '88 crx w/ a 94 b18b. I need to go to the ref soon. How have your experiences been? Anything you can tell me or look out for when I go?

As for the idle, mine idled high after I did the swap - I replaced the IACV, fast idle valve, checked TPS voltage, etc. I didn't check for vacuum leaks because all were properly hooked up. As a last resort, I covered the two holes in the throttle body (in front of the butterfly with my fingers) and sprayed carb/choke cleaner around all the vacuum lines and gaskets. Either the car will die if there are no leaks, or it will stumble once the carb cleaner is sucked in. Turned out my crappy Fel Pro throttle body gasket didn't even fit on the entire throttle body - ordered a new one from Acura and everything ran great. Give it a try.

As for O2 sensors, you can try http://www.oxygensensors.com
You can get one for $60-70 (it must be 4 wire b/c you are obd1). Honda wants something like $200 for a sensor!!! Crazy!
Let me know if you figure it out.
Rob

 

well, the ref is off of power in road, and frankly there not the easiest folks to deal with. One of the guys, i would not mund bashing his head into the counter a few times. He gotall pissed at me because i backed the timeing past the alloted 2 degrees. telling me that it was a crime and stuff. I just dont think that he liked my car, he was talking about his mopar the entire time, oh well. But yeah if you need to know how to get there, IM me and i can give you directions or something. Thanks for all the help, im going to try all this stuff on my next day off. I have got to get this thing running correctly. Allso i forgot to mention that there are resistors in line to the o2 sensor. The guy I bought the car from said that they are jus there for the 02 heater, so i checked the code and it was right, well i think that it says, o2 sensor/heater. do you guys think that this could be the reason, allso when i had bought it, the resistors that were there were burnt, so I had to replace them. Let me know. Allso all connections are soldered.


Rob

 

in my last entry to this topic i said i replaced my o2 sensor. that was not the problem it was my MAP sensor. sorry i had a idiot moment.

 

haa haa its okay, thanks all the same!


Rob

 

anyone think that it may have anything to do with the resistors i mentioned?


Rob

 

there is a screw on your throtle body that adjust the tps sensor trying losening it this may solve your problem

 

your not talking about the idle air screw right?


Rob

 

yes i am

 

Okay so i now have time to work on the stupid car, and I went out there and I coverd the two holes like that one guy said and it dies, so i guess its not getting air from anywhwere else. Allso, should the car die if you turn that idle air screw all the way in? Because mine doesnt, it keeps running.


Rob

 

Okay well I just checked the cam timing out, its straight. any other thgouhts?


Rob

 

Well, I guess that since it did die, sounds like you don't have a vacuum leak. As for the idle screw, I don't know.
Did you say that it was still throwing a code for O2 sensor? If so, the first thing I would do is fix the problem that's producing the code - whether this is the O2 sensor itself, or the resistors that you talk about. My O2 sensor is directly wired up to my ECU conversion harness - no resistors inline. How's yours wired up (to a conversion harness?)?

Do you have the number of the smog ref? I think I'll try my luck out
Thanks,
Rob