d16y8 swap with idle problems

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bandolero

New Member
Hi, I have a 92 Honda civic dx with a automatic tranny. My engine blow up so I decide to do a engine and tranny swap. I use a 97 civic engine d16y8 with 5 speed tranny. So I did the swap but now I have idle problem. The idle jump up and down from 1000 rpm to 2000 rpm. Let me explain all I did to do this swap. Before I put the engine I replace a lot of parts. Here the list for the parts I replace.

Valve cover gasket
Valve stem seals
Head gasket
Oil pan gasket
Cam shaft seal
Crank shaft seal
Rear main seal
Timing belt
Water pump
Tensioner belt
Intake manifold gasket
Exhaust manifold gasket
Transmission seals
Cutch kit
Flywheel
Clutch slave cylinder
Sparkplug & wires
Distributor cap & rotor
Pcv valve
Thermostat
Radiator & cap

I took everything a part and took my time to put it back together. I recheck everything. I used my original engine harness obd1 and use a p28 ecu.

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I read a post on another forum about how to put a d16y8 intake manifold into a d16z6 so I use that info to make my y8 manifold work with my obd1 setup. The only thing is that I didn’t have the z6 throttle body so I use the one from my old engine 1.5 non vtec and I don’t now if that my idle problems because the map sensor is not mounted on top of the TB is in the fire wall. If you look closer the intake manifold you could see where I mount the purge control solenoid on back of the manifold and the IAT sensor on the side. Another thing is that I still using the IACV from the y8 engine and not sure if the one from the z6 will fix my idle problem. Also the TB and FITV are from my old 1.5 engine.


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Now about the wire harness everything was plug and play. I only did the wire for the vtec and was only from the vtec valve to the connector next to the battery, from there to the ecu was already rewire from factory. So I don’t think there a problem is with the wires. Here are a few thing that I already check.

Timing belt is right on
Bleed radiator
Clean the IACV
Clean the FITV
Bypass the coolant hose
Check for vacum leaks
Check the sparkplugs and gap

I really don’t now what to do. This idle problem is making me crazy. Other then that the car run really good. I took it around the block and has a lot of power and that intake sound real loud when that vtec engage. All I need to do is fix that idle problem so if somebody could help me please.

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Very nice, clean swap. Looks great!

Sorry, I don't have an equaly great answer for you. All I can say is, it is deffinatly possible that the map sensor is different and thus reporting *incorrect* data. I'm also not completely sure about the IACV compatability either. I've wondered about that because of some things with my car, but never took the time to look it up. I'm going to try and see what I can find. In the mean time, try putting the other map sensor on. You can just plug the hose in like the firewall mount version your using now. I've done it, and it will function normally.

By the way, welcome to Hondaswap! Might I ask where your from? Your english seems a little broken, but completely understandable none the less.
 
ok guys i swap the map sensor for another one and still do the same thing but i notice that when i disconect the vacum hose from the map sensor the idle stay on 1000 rpm. so i check both map sensor and they are in good working order. also i forgot to tell you that im using an automatic p28 ecu. i now that not the problem but maybe im wrong. here a link for a video i took this morning so u could see and hear the idle problem that i have.

Video of D16Y8 IDLE PROBLEMS - Photobucket - Video and Image Hosting
 
It could have something to do with the ecu. Maybe try getting a manual tranny ecu.
 
Yeah there's a good chance it is the ECU. Also, double check your wiring in case you had to switch any sensor plugs around. Make sure your map and tps plugs arn't accidentally switched. I'm not familiar with this swap, like, I've never done it, but I would assume a manual transmission, different displacement motor will need a manual ECU ment for that motor. The most cost effective fix will probably be to chip the ECU you have. This involves opening the ECU and soldering a new Integrated Circuit (IC) chip that holds information about fuel maps, timing advance, vtec crossover, etc. You can convert your P28 to manual, and put D16 fuel maps on it.

Research: Welcome to PGMFI
Purchase: Crome, TurboEdit, Uberdata --- DIY Honda ECU tuning and chipping resources, products write-ups and links. Widebands, Fuel Pumps, Intercoolers, ECU Chipping, Wideband Tuning & more
 
ok i check everything and still doing the same shiet. i read on this forum that if you put your hand over the TB and the engine turn off it mean that there no vacuum leaks.

so i try it and the engine keep runing so i search again for vacuum leak and i found something interresting. sound like is inhaling air between the head and intake manifold. the gasket is new so i really dont know if that suppost to sound like that.
 
get some incense or if you smoke, blow a thick cloud by that gasket and see if it sucks air in. that's the best way to check for vac leaks.

if you find you have to replace it, i recommend the hondata intake manifold gasket to reduce incomming air temps
 
ya man. The hondata gasket is nice and if you ever have to take the engine apart you can reuse it.
 
Nice swap man!.. I did the same thing.. I actually converted my automatic to 5 speed and my idle does the same. I am so irritated off of it. let me know if it was a vacume leak for you? thanks
 
thank you guys for all your help, i got the idle problem fix. i swap the y8 intake manifold for the one from my old d15 engine and it works great. thanks for your help
 
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