ODB2 to OBD1 problems

[sw_vile]

So, I jumped my '96 240 from OBD2 to OBD1 using and Enthalpy harness and the MAF and ECU out of a 93. Drove the car on and off for about 2 weeks with no issues, and I mean none at all.

But, starting earlier this week the car would not start early in the mourning when it was cool outside but when I got home from work each day it would fire up on the first try without hesitation. But not needing the car as a DD I didn't really worry about it. Yesterday I took the car out for a long drive went over 200 miles getting between 25 to 30 miles to the gallon. It ran good and pulled hard. This mourning I tried to drive it and ran into the same problem, no cold start. When I got home from work this afternoon the problem was still there.

Here's where the fun begins. I checked everything it had spark, fuel, all the ground were good, MAF connection was good, and replaced the coolant temp sensor with a known good one off of a friends old car. Still the same problem, no start. So after messing with it for a couple hours I decided to swap the ECU, Car fired up. But ran like crap. Idles at around 2000rpm and runs rich as balls.

So I started troubled shooting, pull the MAF plug and TPS plug with no change. Then I unplugged the big connector on the front of the intake manifold. Car idled normal but kept shutting off and being extremely difficult to start back (I had to pull the battery terminal everytime) Then for S&G's I pulled the MAF off of my '95 Altima and put it on the 240. Car runs great! Idles perfect, doesn't run rich and has yet to cut off or even try (i've been listening to it run for a little over 30 minutes) But if I go out and plug the connector on the intake manifold back in the car idles up around 2000rpm. Which is strange.

Anyone have any ideas on what I should, or what I should do to fix these problems? I'm fresh out of ideas.

Or should I just call it problem fixed until the car starts acting up again?

[OutToWinPAHC]

I wonder what this connector is for. I wonder if you have a really bad IAC that needs cleaning.

[sw_vile]

I wonder the same thing. I believe it has something to do with the emissions related crap that on the bottom of the manifold, but I'm not 100% on that yet. It struck me as odd that the car ran great for 2 weeks with everything still plugged it, only in the last 24hrs it has become an issue.

Later today or this week, I'm going to disassemble the intake mani clean everything, delete all the emissions and see where that takes me, I've also debated on just buying the Xcessive manifold and being done with it.

I just really hope that someone can help me out with these issues. I know there are a ton of people who have done this turbocharging a car but not many who have done it and left the car N/A.


Edit: I tried to drive it to the store earlier and it left me stranded. Car started running like s***, tach started jumping all over the place and finnally it just shut off and wouldn't start back.