This will be a long post that explains how I created these problems and what I did to fix them so when somebody SEARCHES the archives, like they should, it might help them to fix their problems.

I did a DPFI-MPFI swap on my '90 CRX DX about a month ago, this was my first step in upgrading the stock D15B2 motor. I had read many posts in the archives and FAQs and I had the parts from a motor that I picked up cheap, so I thought I would give this a try.
After I finished the install and wiring I cranked it up and got a CEL code 4 (crank angle sensor). So I called the guy who helped me with my wiring harness and he said the distributor plugs might be backward in the harness, so I switched them around, but I still had the code 4, so I switched them back to their original position. I wasn't sure how good the distributor was so I ordered a new one from Distributor King, put it in and still code 4 so I swapped the wires again then back again. I tried another ecu same thing. I swapped the wires at the distributor every time I tried something new, I also reset the ecu with any attempt. These wires at the distributor are the B10 and B12 wires at the ecu. What finally fixed the code 4 was depinning B10 and B12 and pushing the small tabs on the side of the pins that make contact with the ecu pins.
With the code gone now I had to set the ignition timing but it was to far retarded and I had read about the timing belt jumping a tooth and with the way the car was running after the swap it sounded like this could be it. Also with the crankshaft pulley at TDC the marks on the cam pulley didn't line up with the indicator so I jump the belt a tooth and was able to set the ignition timing.
This did OK until I drove on the Interstate at 75mph @ 3400 rpms for a little while then the CEL came on for code 1(oxygen sensor). I bought a new one but the same thing would happen every time I drove over 3K rpms for a little while and I commute 42 miles(one way) to work everyday on the interstate. I looked in the archives and found others with the same problems but I couldn't find any that had fixed it. I posted the problem and a few members suggested different things but I couldn't make it right.
Last weekend my wife and kids were gone to Disneyworld so I had some uninterrupted time to track this down. I had read 1 post that said if your B10 and B12 are backwards you will run way retarded, so I put this on my list of things to check but I didn't give it much thought because I thought it would give me that code 4 if they were backwards. So I did this before I ever started the car so I could eliminate this from my list, but when I started the car I didn't get a CEL. I checked my ignition timing and it was to high to adjust with the distributor so I jumped a tooth back where it had been originally. Then I set my timing at 18 BTDC (the center of the 3 marks) and ran it. Now I know what it really feels like with MPFI and yes, it is noticeable.
So to wrap this up, check your wiring, this is what most people post when you have problems and they are right. If it worked before you changed something, start there. I ended up buying a distributor, ecu, O2 sensor, vacuum hoses, spark plugs, plug wires and a voltage meter that I didn't have to have (but I would have sooner or later). And on top of that for not checking things out better my punishment for myself is writing this long explanation. If this swap would have gone right I would have been happier but now that it is right and I learned a little bit I guess it didn't kill me and maybe this will help someone else.

Check wiring and pin connections at ecu, check grounds, check vacuum, reset your ecu each time you change something and get a CEL, check cam timing(my mark is a little before the indicator), set ignition timing by the book.

Also if you do start a thread, put something in the title that has to do with your question or problem so that those that search later can find the information. Don't put something like "I have a question" or"help me please" or anything useless to somebody else searching. And if you reply to someone else be specific with your information, this is what I believe H-T was meant for. I read a lot of archived posts and the FAQs before I ever joined or posted a thread you will learn lot from some members on here and some not so much. You will get to know who to listen to and who just like to see their name on the computer. State your problem clearly and everything you have done to "fix" it(that's where I messed up), a bruised ego is better than a Honda that isn't running at it peak performance.

 

Why do you have to adjust the timing when doing this swap? The new distributor can only go in the same way the old one came out.

I'm going to finally be doing this at the beginning of next week.

I see a lot of people having trouble with this swap..it seems fairly straight forward...

 

You have to change the distributor out to put the SI one in. The cam has an off centered slot in it that the dist. foot goes in but you still have to move the dist. forward or backwards in the bolt slots that hold it in and the foot on it moves pretty easily so yes you will have to set your ignition timing.
It should be fairly easy unless you do something wrong like I did and then make it worse "fixing it".

 

If you put the SI one in exactly how you took the old one out then how will it be out of time?

You can spin the thing on the dizzy that goes into the cam...it can only go in one way...when it slides in...it means it was the same as the original dizzy.

I've changed dizzy's before and did it the way above and have never had a problem with timing.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DenzComp &raquo;</TD></TR><TR><TD CLASS="quote">If you put the SI one in exactly how you took the old one out then how will it be out of time?

You can spin the thing on the dizzy that goes into the cam...it can only go in one way...when it slides in...it means it was the same as the original dizzy.

I've changed dizzy's before and did it the way above and have never had a problem with timing.</TD></TR></TABLE>

You are stupid sir. He is talking about ignition timing not cam timing Just look up the proper sequence for setting the timing. You need a timing light. If you just pop a new dizzy how do you know its at 16 or 18 degrees or whatever you need for that engine?

 

I don't understand how going to MPFI would change your timing....I'm still a noob, so inform me.

 

"If you just pop a new dizzy how do you know its at 16 or 18 degrees or whatever you need for that engine?"

You know it's at whatever degree it was when you took the old one off....As long as you don't spin the cam why would it have changed?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DenzComp &raquo;</TD></TR><TR><TD CLASS="quote">As long as you don't spin the cam why would it have changed?</TD></TR></TABLE>

There are TWO types of timing at play when you take off the dizzy and replace it. Sure the cam timing will still be on, but the new dizzy may not have the same ignition timing that the old one had. Thus you'll need to re-time the ignition timing, and the best way to do that is with a timing light.

 

The shaft in the distributor and cam shaft will always be lined up correctly, but the sensor that fires the ignition is stationary in the distributor housing. So by rotating the housing clockwise or counter clockwise you are setting the point where the ignition fires. If you don't use a timing gun to do this, you may not be getting the most effecient setting, it will run but not like it was designed to. That is why there are slots and not round holes in the distributor.

 

Wow...thanks for the info. As I said...I am still new to working on my own vehicles...Ive replaced my dizzy once with one from the junkyard and just popped it on...must've been lucky.

Ya learn something new everyday.