s13 sr20det two dead cylinders

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SavageS13
 

Posts: 6
Joined: Fri Dec 30, 2011 1:26 pm

s13 sr20det two dead cylinders

Post by SavageS13 »

Hey guys,

Sorry i couldnt post this in the "mechanical/sensor issue" section of the forum as i do not have access to it...

Trying to get my brothers project finally done..

Heres the short story

s13 sr20det black top
Freddy intake manifold. stock everything accept for Arp headstuds and freshly machined head. tubular exhaust manifold with stock t25.
nistune board
Engine is firing on cylinders 2 and 3.

Compression is 150psi across the board cold.

In an attempt to figure this thing out this is what ive discovered so far...
I pulled the coil off cylinder 1, leaving the plug in and disconnecting the injector clip. Grabbed a spark plug and grounded it off the exhaust manifold. Good spark. Now i know dead cylinders have good spark.

return everything to normal, try again, same story 2 dead cylinders. Pull the plug out of cylinder one and i can smell fuel. This does not surprise me as we have checked the entire rail in the past (this has been an on-going issue) by pulling rail, leaving feed and return connected and turning the cas by hand to see spray pattern. all have good pattern with no leaks.

also has a brand new wiring specialties s13 sr20det engine into s14 chassis engine harness.

So my question is,
If the dead cylinders have spark, compression and fuel... what gives? maybe injector drivers on the way out? ignitor bad?

halp!
bachig24u
 

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Joined: Mon Jun 01, 2009 11:46 pm
Location: Campbelltown, NSW
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Re: s13 sr20det two dead cylinders

Post by bachig24u »

ignition point possibly incorrect. needs checking.

sounds like the coil packs are mixed up.
put a timing light on it and see where no.1 fires on the crank timing marks.
if it doesn't line up with stock cranking ignition timing then something is off.

If someone can confirm that these ecu's can trigger individual injectors it may be a possibility during the manifold install that plugs are mixed up.
else the wiring loom needs buzzing out to the injectors and coils to ensure they match up as per the ECU pinouts.

btw, there is no mechanical section..
SavageS13
 

Posts: 6
Joined: Fri Dec 30, 2011 1:26 pm

Re: s13 sr20det two dead cylinders

Post by SavageS13 »

Well heres the kicker with the harness... its brand new by Wiring Specialties designed for the swap. So i cant see plugs getting mixed up. We've also got two different coil packs we've tried.

Everything seems to be pointing towards ECU. It seems like it would be a component that both cylinder one and four relate too. injector drivers? are there coil drivers?
bachig24u
 

Posts: 678
Joined: Mon Jun 01, 2009 11:46 pm
Location: Campbelltown, NSW
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Re: s13 sr20det two dead cylinders

Post by bachig24u »

quote" So my question is,
If the dead cylinders have spark, compression and fuel... what gives? maybe injector drivers on the way out? ignitor bad? "

if all cylinders have fuel and spark, then it seems likely that the spark is miss timed.
hence why you need to confirm that the ECU pins for coils in particular, and worth also checking injectors, that they correctly correspond to the correct physical devices (injs and coilpacks).
SavageS13
 

Posts: 6
Joined: Fri Dec 30, 2011 1:26 pm

Re: s13 sr20det two dead cylinders

Post by SavageS13 »

Will give each one a check tomorrow and update.
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