Blew up my Y8, and a friend had a Y7 sitting around, so I dropped the Y7 into my 96 Civic EX. I used the Y8 intake manifold of course. Anyway, it won't start. I'm getting fuel, and spark, but it's not even sputtering.. Plug wires are in the right order, even tried switching them around for ***** and giggles.. There are some electrical connectors that are not plugged in, like the 2 VTEC ones, because the Y7 insn't VTEC, duh.

Having what sensors plugged into the wrong plugs or what sensors being unplugged will make it not start? Air + Fuel + Spark = Ignition... so wtf?

Any and all help is appreciated.

 

Does the CEL stay ON when the key is turned to ON(II)? If so, pull the codes.

Is the spark bright and blue or weak and orange?

Have you checked whether the cam and crank are synchronized perfectly at TDC1?

How's the compression?

 

what ecu are you using? i'm assuming you are using the ex harness, ex one-plug OBD1-style dizzy (Y7, as well as all other OBD2 dizzys have 2 plugs), ex 2-wire iacv on the ex manifold (Y7 had the 3-wire iacv), with maybe the Y7 ecu?? i'm thinkin the ecu might be lookin for some dizzy and/or iacv signals that aren't there.... have you tried crankin it up with the ex ecu?

 

Wow.... Compression test SUCKED...

#1 = 150
#2 = under 100
#3 = under 60
#4 = under 60

WTF... time to get a refund, bought it less than 90 days ago.

 

Ouch ouch ouch. Those are some bad numbers and yes, I'd be getting a refund. Even if you messed the test up and did it incorrectly you'd hope to see some consistency, but those are just whacked out.

 

maybe you did the test wrong, ive seen a test come similar to that then when done again while holding TB open while cranking it came out almost normal. just a suggestion.

 

I did the test with the battery connected to another car via jumper cables. So it had full cranking power. All 4 spark plugs were removed, the fuel pump relay was pulled, and I had the TB at WOT. I even cranked it wayyy more than I should have.

 

you might want to try adjusting the valves. i've seen tight valves in a junkyard motor

 

The valves would have to be SERIOUSLY out of adjustment to throw the numbers off that far. The only thing I can think of that would make the compression decrease like that is either a bad torque sequence on the head bolts or having the head machined incorrectly. Generally if it was rings you'd see low compression evenly across all 4 and if was a head gasket, you'd see low numbers on two adjacent cylinders. If you really wanted to know where the compression is going, perform a leakdown test.

 

you could try dropping like a tablespoon of oil down into each cylinder, and then do the compression test again. if all your numbers bump up you know the compression rings are toast. if it stays about the same then either your valves are fubared, or you have a massive hg leak into the coolant jacket.

 

just fyi, tps and map can be switched, as well as a few 2-pin circular plugs (including the iacv on the ex) and also again, what ecu are you using?? because if you are using the non-ex ecu, theres some distributor and iacv wiring messed up. have you tried the ex ecu?

oh- and i have seen junkyard D16s valves barely too tight so they never fully closed and it lost all kinds of compression because of it. just perform a valve job to be certain.

 

I just figured that I would bump this old thread from the dead, from 2009, yes, it's 2013 now haha. Anyway I figured that I would post a little bit on honda-tech, bored, something to do... And saw that I had three posts, googled up this thread, so I'm starting here.
Thanks for all the help 4 years ago lol, but heres what happened.

The motor I bought from a junkyard like I stated earlier.
The junkyard said it was a very low mileage good running motor when they got the car.
At some point in time they sold the hood off the car, along with the intake.
We all know that the Y7 intake manifold isn't horizontal like most intake manifolds, its vertical, with the throttle body pointing straight up.
Well, when they sold the hood and intake, they just shoved an old rag in the throttle body to keep water from getting in.
Didn't work..
Water had gotten down in the motor over the years of it sitting in the junkyard, and had rusted either the cylinder walls or the rings, or both, yielding next to no compression.

I took the motor back out of my car, exchanged it for another one, bolted everything back in, hooked everything back up, and viola! Started right up.

Just an update on my first HT topic, and food for thought,
again, thanks for the help!