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xpinoyxmk
12-07-2018, 08:13 PM
Need help.

Little background:

Went in for a car alignment last week, everything was good. Then yesterday I go to start the car and it sounds like a subaru, rev a couple times, very difficult to rev and it breaks up bad, and smoke coming out of the exhaust (heavy fuel smell). Caught me off guard, my assumption is that its running on 3 cylinders, so I go thru the regular procedure.

Spark, begin unplugging each connector to each coil pack, with #1 unplugged nothing changes, all others have a noticeable difference.

Fuel, same with pulling the connector. All have a slight but noticeable difference. Pulled the rail to see if the injectors are leaking or stuck open. They check out all good.

Checked for air/boost leaks, none.

Pulled the valve cover to see if anything was loose or a rocker arm fell off. Nope nothing.

Decided to test to see if anything changed if i pulled the fuel pump fuse. Normally it should die pretty fast... Nope, begins to idle normally except at 2000 rpms and stays running until i try to rev, then it will die. I assume its only running good because the excess fuel is burning off. Also longest i let it run, after pulling the fuel pump fuse, until I would rev it is about 30 sec.

Z32 mafs has been verified good. With it unplugged, there is no change for the better or worse. Also my tuner said the stock fpr's could be the issue.

If anyone has any information that could help, I'd greatly appreciate it.

Details on my car for reference:

180sx, original sr20, gtx2867r, hks 740cc, z32 mafs, enthalpy tune

Edit:
-swapped coil packs between #1 and #2, no change still on #1 unplugged
-replaced spark plugs with bkr7e's, gapped at .028, no change

Unsure if this is related but my fuel pump stopped priming/working for a short time.

e1_griego
12-07-2018, 08:16 PM
Did you swap coil packs around to see if the dead cylinder followed the #1 coilpack? It's a pretty common failure.

xpinoyxmk
12-07-2018, 08:23 PM
Did you swap coil packs around to see if the dead cylinder followed the #1 coilpack? It's a pretty common failure.

Yes I swapped #1 and #2. Still was the same on #1.

Sr20-Vert
12-07-2018, 09:34 PM
Yes I swapped #1 and #2. Still was the same on #1.

Take spark plugs out and check them all

xpinoyxmk
12-08-2018, 10:41 AM
Take spark plugs out and check them all

Ended up replacing them too. No change.

Quiche2192
12-08-2018, 11:55 PM
You getting any codes from the ECU? I'm having the same issue and I've narrowed it down to the knock sensor.

Haven't gotten to it yet, so I'm not 100% sure, but both our cases seem like a knock sensor issue. Breaking up bad when revving. Although for me it only happens under load. Check if your ECU is throwing code 34.

Oh and if your fuel pump stopped priming, it might be an electrical issue. I had the ground on my alternator go bad, which made everything go whack.

jedi03
12-10-2018, 10:54 AM
happened to me when had coupler on intercooler come loose...

xpinoyxmk
12-10-2018, 10:57 AM
You getting any codes from the ECU? I'm having the same issue and I've narrowed it down to the knock sensor.

Haven't gotten to it yet, so I'm not 100% sure, but both our cases seem like a knock sensor issue. Breaking up bad when revving. Although for me it only happens under load. Check if your ECU is throwing code 34.

Oh and if your fuel pump stopped priming, it might be an electrical issue. I had the ground on my alternator go bad, which made everything go whack.

No way to check codes. Your issue is most likely different since its only under load.

happened to me when had coupler on intercooler come loose...

All couplers are good. No leaks.

xpinoyxmk
12-12-2018, 11:35 AM
Just an update.

Started the car for 10sec then pulled all plugs to see if any were coated with gas. #1 was. Proceeded to switch injector #1 with #2 and retest. Again ran for 10sec and pulled 1 & 2 plugs. This time #2 plug was coated with gas. Removed all injectors and having them serviced locally.

inopsey
12-21-2018, 04:20 PM
what is the compression on that engine??

xpinoyxmk
12-22-2018, 02:34 PM
Haven't done a compression test yet.

Just put the injectors back in after service, did an oil change (gas smell in oil), and reconnected the battery.

Ran good on first start up so I shut it off. Rechecked the oil capacity, topped it off, then went to restart and its running like crap again.

Threw in some fresh plugs gapped at .028 and it made no difference.

Just noticed the red light on my ecu stays on while running and my fuel pump definitely doesn't prime as long as it should be.

Bad ecu maybe?