ZC DOHC 1991 Hatchback Transplant - Epilog

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Wiring issue with O2 sensor corrected. No CEL error codes with the P06 ECU. Time for a test drive.

Runs kinda limp with the stock P06 map - sounds a little on the lean side. Took it real easy and went to car wash and gas store. Stalled out on the way back home - re-started after a couple of trys. Throwing CEL code 15 "Ignition Output Signal missing or defective ignition output signal". Hmmm - dizzy or wiring?

Idle problem still there. I loosened the idle screw and attempted to adjust when I set the distributor timinig. Even with the set screw backed away from the lever on the throttle body the idle won't come down below 950 RPM. Either a vacum leak somewhere or the butterfly isn't closing correctly.

Will work that next week.

Hood closes with top timing belt cover off. Not sure what I"m going to do about that yet - no big thing for now.
 
Have a list of things to do this weekend - glad it's another 3 day weekend, I have Friday off.

  • Change out fuel pump
  • Check fuel pressure
  • Clean up wiring to main distributor connector - clear the CEL 15 code
  • Pull throttle body and correct idle condition
  • Change exhaust hangers behind cat (have polyurethane replacements)
  • Install socket and modified P29 chip to P06 ECU
  • First oil change
  • Cleanup wiring around relays behind passenger side headlight
  • Check cam timing - had to swing dizzy pretty far towards advance to get timing on the mark.
Need to get it ready for state inspection and a run on the emissions dyno.

Wish it wasn't so phuking hot outside.......

Some future stuff - decide on the hood so I can install upper timing belt / cam pulley cover.

Also need to hit the salvage yards and scrounge up the 2 wire connector to the distributor and the 4 wire connector for the O2 sensor. Didn't have one so I hard wired the O2 sensor for now.
 
Still vote ZC hood...

js-replica-poly-90-91_01.jpg
 
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How ironic. :lol:
other than the hood this is how I imagined my ride after it's done.

good luck with the trouble shooting man!
Ok ok ok, I'll hump out the hood - no, not hump on the hood. It does look good.

Troubleshooting went well. Driving it to work now, rental car returned yesterday. Running pretty limp. Had to advance dizzy almost to the stop towards advance to get timing on the 16 degree mark. And it runs like the intake cam is retarded - I'll work with that this weekend. Also look at fuel pressure after changing out the fuel pump. Just preventative maintenance - also will change out the main fuel/ignition/ECU relay.

Good luck with your troublshooting Hoss! I have some good schematics, if you need any let me know. Have one blown up into a 4 page tile printout in landscape, then trimmed edges for correct matching overlap and taped them together to make one big picture that is easy to read.

With a good schematic (like Helms) that's large enough to read and a test meter the wiring ain't too bad to work.
 
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Hmmm. Timing belt too long or too short? You must have aligned it to TDC and checked the marks. Your cam gears maybe? But they looked so bang on to the stock ones. I don't know what else could throw the timing wayy off.

Nice to hear its driving. How do your mounts feel? I love my stiff ones.
 
Hmmm. Timing belt too long or too short? You must have aligned it to TDC and checked the marks. Your cam gears maybe? But they looked so bang on to the stock ones. I don't know what else could throw the timing wayy off.

Nice to hear its driving. How do your mounts feel? I love my stiff ones.

I think I figured it out. We measured the cam timing corrections in degrees. Both cams were retarded, so they were advanced with the adjustable pulleys. The problem is I may have read the correction right off the indexing scale on the pulleys and matched the readings from the protractor. The protractor reads in degrees, while the cam pulley indesing marks are in crankshaft degrees meaning it takes 2 marks to make 1 degree of cam timing change. We probably read the corrections from the cams in cam degrees and corrected using crankshaft degrees. Duh!!! So both cams are retarded. Actually, it's the mechanic that's retarded.I'll confirm that this weekend and advance the cams up to nominal.That will wake it up bigtime.Hoping the chip & socket arrive by Saturday. Winfab Tuning P29 mapped chip is on the way for the P06 ECU.

Like the motor mounts. Real stiff - in conjunction with the SECO clutch disc and Competition Clutch pressure plate the car launches much better. Let the clutch out now in 1st gear and it takes off. Fairly easy to spin tires.
 
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yeah man! good job. shoot me an email with the helms schematic will ya?
never hurts to have too much information.

taco151984@gmail
 
yeah man! good job. shoot me an email with the helms schematic will ya?
never hurts to have too much information.

taco151984@gmail
Tell me what ya got? Chassis year and model? I know it's a CRX. Also, what did you put into it? OBD1? Did you go from OBD0 to OBD1 like I did? Then I'll pick the right schmatics from what I have.

I might just print you a set and you can PM me your mailing address if you want. Just got a shipment of printer ink cartriges today and have plenty of paper.

Let me know. The Helms files are large adobe. I also may be able to put them on a server and give you access to download them.
 
Many parts arrived today. Coolant reservior tank (other one leaks), extra MAP sensor (used), and the Winfab Tuning P29 chipset.

Pulled the P06-A01 ECU and put it on the bench. Had to use a vacum type solder remover to clear the holes for the new components. I put pictures of this in the front of the thread in post #7.

Re-installed the ECU and hit the starter. Fired right up and I could tell right away it was richer - the idle was slower and steady. Whacked the throttle a couple of times and it sounded much healthier. Oh boy! Time for another test drive. What a HUGE difference. That chipset cost $15.99 + $12.00 shipping and handling.

Runs way better - stronger than the D16A6 ever was. Still think there's more to be had - cams are probably retarded 2 or 3 degrees. I'll check that tomorrow.

Starts pulling hard at 4k and sounds real sweet at 5k RPM - don't want to push it too hard yet as the new piston rings are seating. Has a little over 70 miles on it.

Also ordered a full width, 2 row core, twin fan, aluminum radiator today.
 
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What break-in process are you using?
Not sure how to characterize it as a process.

Old school method - run it during break in how your going to run it when it's broken in - but, take it easy in the process.

Cranked it over with fuel pump disconnected and spark plugs out until the oil pressure idiot light went out. Installed plugs, connected fuel pump and fired it up and let it idle for 20 minutes. 5 hour cool down, then retorqued head. Checked fluid levels.

Drove it easy for the first 25 miles or so, jumped on it a couple of times.

The thing not to do is bog it or load it down at WOT - don't let the manifold vacum drop down too low - don't build excessive heat in the engine. So, when I wind it up to 5k or so, it's only in 2nd and 3rd gear and only for a short duration - once it hit's 5k back off it and shift into 4th and then 5th gear then cruise easy. It saw 6k a couple of times today for an instant.

Is that what you mean? I guess it's the "Run it Hard" method.

http://www.mototuneusa.com/break_in_secrets.htm

I've had good results with this technique with many engines. When I can, I'll run them rich at first, especially the nito motors. But, the race engines have more clearance's internally (in addition to being more robust mechanically) overall than do street auto engines - so while they operate in a more extreme environment, they also are built to take it. For the Kart engines and dirt bikes, pretty much the same as the ZC - only with the jetting fattened up a little.
 
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Yeah that's what I was asking. That is pretty much the same method I used when breaking my engine in.
 
Just a little short of "Run it like you stole it"! ;) Heat is the key. You don't want excessive heat build up - that's when the problems start - gauling and seizing. Gotta keep things short of that. Can't let the parts "Grow" or expand from heat too quickly or too much.

The school of thought is - if you're going to run it hard when broken in, you can break it in too easy and have problems when you pour the coals to it later on, if it's not stretched out a little during break in..

I'm going to check cam timing in a little while. I know the intake is retarded from when I set the timing. The exhaust is probably retarded as well as the corrections were towards advance when I put it together. That will be another huge wake up. Also gotta pull the throttle body and get the fast idle issue resolved.
 
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Well well, checked the cam timing and timing mark increments. They are in single degrees of cam timing which equates to 2 degrees on the crank. Cams were right - but since it took the dizzy a little past center to get timing correct, I advanced the intake cam timing by 2 degrees and reset dizzy position with timing light. Still takes just a little towards advance from midpoint to hit 16 degrees on the crank. With ECU in service mode of course.

Nice improvement - quieter heading down the block from my house and it pulls a lot better above 4k. Pulls steady in 4th gear now between 80 & 100 mph.

Starting to find the "Rumble in the Jungle" this build should deliver. It'll walk away from the D16A6 now. I hammered it in 2nd gear on the freeway access road and wound it up pretty tight - nice - pulls all the way up the hill.

On the way back home it started acting wierd in the low end, running rough - seems like the TPS may have some bad spot on it - time to change it.
 
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Bump - updates to post #8 "The Results". More to follow on radiator and fan installation, wiring, fan relays, etc.
 
this is probably one of the most well documented build threads i have seen. awesome job. not a crazy swap, but you took the time to do it right the first time. rep and :thumbsup: for you, sir.
 
this is probably one of the most well documented build threads i have seen. awesome job. not a crazy swap, but you took the time to do it right the first time. rep and :thumbsup: for you, sir.
Thank you, I genuinely appreciate that. That was my intent going in, to document the thing - there were many times having the camera there and having to stop and take pictures was an added effort.

Lots of pictures still aren't posted and I'll be adding them over time as well as the body work phase - how to and what I did. Doing the project is great, but it's really just as rewarding to maybe help somebody else - even if just a little.

Documenting was time well spent as online forums have been a wealth of knowledge - so, hopefully I can give some back. I mainly targeted the new tuner - trying to share technique's that I have picked up over the years from others. My first Honda, but not my first rodeo.

Once, the mechanical is done, and that should be this year, the aestetic will commence. Interior and body. There's going to some custom work, the hood and the wing - that's probably it and of course paint which will mean repair of minor hail damage and a few small dents and such to straighten it out - then a paint job. The custom work will be somehow have a touch of Old School - that was somewhat the theme with the ZC build - this is how it was done 10 years ago - a ZC. When the hood and wing are shaped and other body work done it's going to get something - not sure yet. Something like fill in the hatch door between the tail lights or something - maybe change the lines on the hood. Nothing too extreme, but something custom and unique.

The intent here was to do it right and do it once, then drive it till I retire. Then I'll probably start another project build just for fun.

I consider it a "Real" hotrod now, even as a Stage 1 build - it runs good - very pleased with the results and choices. Hit the bullseye with it. It's a lot more fun to drive now - when some jerk is riding my ass on the freeway on-ramp, just roll it on in 3rd gear and they begin to shrink in the rear view mirror.......mee likes that. :cool:

A little touch of Old School style similar to Cobra's car: Stallone's Stolen Cobra Car | Celebrity Photos | TMZ.com Just a touch, where they look at it a while to figure out exactly what was changed. The aluminum work in the trunk is sweet.
 
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