OK.... So I corrected the start circuit, and grounded pin 50. There was NOT a wire for pin 50 in the plug, so I added one. I took pictures of the location if for some reason there should've already been a wire there. 

 

After about 10 min of driving the CEL came on. Also, the engine died When rolling in nuetral on a freeway offramp, I didn't realize it until I was at the stoplight. 

 

Had the codes read, it was the same P1500 for the cooling fan relay, and P0505 IAC malfunction. Those were the ONLY codes thrown, so I am optimistic about the AT/MT issue. Also, I've never gotten the IAC code before.

 

I am thinking, disassemble/clean the IAC, reassemble, and see what happens. I'm pretty confident there are no vacuum leaks etc. 

 

Suggestions?

 

Nice. I know I've had to add them before on some later ones, but I thought I'd seen some earlier (96-97) that had the pin. But it sounds like you've got it all sorted out, as far as that's concerned.

 

 

Changing the ECU to think it's an MT will change some of the maps for when the IAC opens and such, but AFAIK it doesn't effect how it operates, so it shouldn't require any re-wiring or anything. So yea, clear the code, clean the valve up, and see if it happens again. It may have just been a coincidence.

IAC code may be coming up becuase the nuetral switch is not hooked up?

 

Doesn't know when to coast or keep the idle up?

Ok. Cleaned the IAC. Found a huge split in the large main hose coming from the crankcase for the PCV. Fixed that. Put it all back together and fired it up. Started fine, so far no codes. I will update after today's journeys. I expect the P1500 at some point. I will fix that when everything else is dealt with. The idle is not smooth either. It is breathing a few hundred rpm pretty contistantly. Sounds like it has a lopey cam idle. Possibly from the light FW? I dunno, it has an ACT Streetlight FW in there. I think it weighs between 10-12lbs as opposed to the stock one which is in the 30lb ballpark if I remember.

Edited May 2, 201312 yr by obk25xt

IAC code may be coming up becuase the nuetral switch is not hooked up? Doesn't know when to coast or keep the idle up?

 

Maybe? Also could this be giving the lopey idle?

Edited April 28, 201312 yr by obk25xt

Ok. So the CEL lit the second the car moved. It idled/revved/ran without issue for nearly an hour. The second I put it in gear and moved, lit up. So I'm thinkin there is somethin happening withe the vss/neutral switch etc. I will have the code read and report back. The engine breathing leads me to believe the neutral switch is probly not hooked up correctly which is why it's searching for idle. I dunno.

Edited April 28, 201312 yr by obk25xt

P0302, P0304..... I don't understand. Misfire on cyl 2 and 4???

 

I am thoroughly confused at this point.....

Edited April 28, 201312 yr by obk25xt

OK! My own incompetence as a mechanic is the cause of some of my issue......

 

So I was chasing down neutral switch wiring, and I decided the intake was in my way, so I removed it. While testing and generally looking for the problem I noticed that after cleaning the IAC, I FORGOT TO HOOKUP THE VACUUM LINE TO THE MAP..... Dammit....

 

So that explains the erratic idle and most likely the misfire too. 

 

I am back to a smooth idle, and we will see how long before the CEL comes on again. HOPEFULLY it will only be the P1500 code this time. 

 

THANK YOU USMB, I will update as I learn...

 

Spencer

CEL lit after a couple hours today as expected. The ONLY code I am getting now (so far) is P1500. This pleases me.....

 

So I need to address the cooling fan relay issue. I know there have been some diagrams posted on how to wire one in etc. Is there already a relay to the EA cooling fan that I can just unhook the signal wire from the thermo switch and hook up the EJ ECU signal wire? I'm sure there must be something that easy. It would hopefully shut my CEL up for good....

 

THANK YOU.....

The stock EA82 electric fan has a power relay, and then the ground wire for the fan runs directly through the thermoswitch. I don't think there's an easy way to wire that in.

 

But yea, you could definitely just grab a generic relay, and hook the control circuit to power on one side and the other side to the ECU signal. It wouldn't have any idea if the switched circuit was hooked up to anything (if you don't want it to).

I am now reading/learning about relays.

 

You're saying the control circuit needs to be hooked to power (+) on one side, and the other side to the ECU signal? The little but of reading I'm doing suggests that I'd hook one side of the control circuit to ground (-) and the other side to the signal (ECU).

 

Is the ECU signal sent by completing a ground? I am going to wire in a relay tomorrow. I'd sure like to do it right the first time.

 

I'm most likely going to wire the fan up to be controlled by the ECU, but if I don't, would it be necessary to route constant 12v to the power in side of the relay? Or will the ECU be satisfied if just the control side of the relay is hooked up?

 

I guess what I'm asking is can I do this with a simple 2 wire job?

ECU signal is indeed a ground

 

and yes, it definitely could be a 2 write job

Relay installed.....

 

Fingers crossed....

 

Should be 100% at this point folks, I'll report back.....

Well, so far so good. This is the longest I've gone without the CEL since the swap. I think WE have handled this one fellas....

 

THANK YOU for your guidance. 

 

Spencer

Excellent! And you didn't need to buy a new ECU!

Excellent! And you didn't need to buy a new ECU!

 

Nope!

 

All has been going well, went 5 days without any codes, then it threw a P0505 yesterday (IAC malfunction). I was really rodding on it though, like really mashing hard in the 5500-6500 RPM range and holding it there for a lil bit. I dunno if that may have something to do with it. I cleared the code and it hasn't reappeared yet so we'll see. Maybe it was just a phantom thing.....

Just an update.... Car has NOT thrown another CEL since all these issues were sorted out..... Good to go......

So I need to address the cooling fan relay issue. I know there have been some diagrams posted on how to wire one in etc. Is there already a relay to the EA cooling fan that I can just unhook the signal wire from the thermo switch and hook up the EJ ECU signal wire?

 

ECU fan signal wire can be connected to the yellow wire at the A/C relay.............OR............

 

if your car doesn't have A/C, simply disconnect the thermoswitch in the radiator, and hook the ECU signal wire to the yellow wire that grounds the fan.  But this leave teh ECU grounding the full fan load, not just a relay.

I just wired in a dummy relay to the ecu. I'm using the ea thermoswitch to control the fan. So far so good no issues whatsoever.

I just wired in a dummy relay to the ecu. I'm using the ea thermoswitch to control the fan. So far so good no issues whatsoever.

 

?????

 

Why would you trust a switch known to fail over the ECU to control???

 

I also don't like the switch being in the radiator, because it's monitoring the radiator temp, not the actual temp of the engine.

 

You installed a relay.  Why not wire it up to actually control the fan?