2jz breaking up under load

[2js1493]

Hey guys so after getting my car together( 2jzgte non vvti) the first problem is it's running really rich but fuel pressure and all checks good also it breaks up really bad after 1/4 throttle basically when the car starts making boost it falls on it's face. If I stay under 1/4 throttle ( making now boost) it can be driving fine any ideas?

[1988montecarloss]

bad plugs or coils? plug gap too big? boost leak?

those would be the first things id check

[2js1493]

Just put the plugs in the other day and have coils on order hoping that's it. I pulled the intercooler boot and it would drive fine . Driving me nuts

[1988montecarloss]

Originally Posted by 2js1493

Just put the plugs in the other day and have coils on order hoping that's it. I pulled the intercooler boot and it would drive fine . Driving me nuts

check all wiring to the coils as well, had a similar issue with my car last year that ended up being a bad ground on the coil harness

[2js1493]

I hope that's not it it has a brand new wiring specialties harness that I installed a month ago or so

[RB25GUY]

Did you clean all the grounds before? have you checked you fuel pump? checked for injs leaks?.....

[2js1493]

Fuel pump is brand new don't think the injectors are leaking but I took the ecu apart today and it's full of corrosion some of the capacitors are leaking. Think that's my problem I ordered one anyway

[jr_ss]

Get it tuned.

[LoneWolfK16]

Make sure you ecu connector harness is tight.

There should be a bolt on there.

If tightening it doesn't work, check the actual pins and connections.

[landins13]

Google, JZ high boost misfire. The engines have spark issues and the more psi the worse it gets. My vvti 1jz used to break up really badly over 14psi, colder plugs, new coil packs and wires did the trick.

[2js1493]

Update put in on new coil packs and replace the ecu still havr the same issue

[1988montecarloss]

is it stock turbos on a stock ecu or has it been modified?

try tightening your spark plug gap

[jr_ss]

Have you replaced the Igniter?

[2js1493]

It's single turbo on stock ecu spark plug gap is at .26 and the igniter I u bought a while back used.

[CompleteXen]

Originally Posted by 2js1493

It's single turbo on stock ecu spark plug gap is at .26 and the igniter I u bought a while back used.

What turbo and boost levels are you trying to run. "Single Turbo on stock ecu" should've been the no brainer. The ECU's are capable of somewhat dealing with single turbos on stock ecu's but only if they are small turbos. I've seen a few guys get lucky at our shop with S363's at around 8-12psi but they have issues breaking up inconsistently.

The stock ecu is not meant to handle a single turbo. Most the guys who have gotten away with it are running MAF's and even then their AFR's are trash.

Get a standalone, get a tune. If the problem persists check your ignitors or MAP if applicable. If money is an issue you can get an AEM EMS V1 for an EVO or Honda do a slight modification to the ecu, custom harness from the junkyard and have a cheapo $400 standalone.

[CompleteXen]

Originally Posted by 2js1493

running really rich
breaks up really bad after 1/4 throttle
car starts making boost it falls on it's face

Use your brain, a tiny bit of searching and common sense could've helped you here.

2J's run pretty rich stock, thats why most guys can get away with running higher boost levels than stock or going to a small single. Breaking up really bad after 1/4 throttle is because lack of tune, you're attempting to run a stock fuel/ign map with a single turbo. Falls on its face during boost? Come on man, stock tune.

The stock ignition system can handle a good bit of boost for what it is, not 30psi kind've power but you can get up to 20 without pushing its limits.


Sorry for the double post.

[1988montecarloss]

There's your problem, get a proper tune done on it

[2js1493]

Starting to realize standalone is the only option. Question is do you guys think I can get away with a piggyback module or do i need to go full standalone. Money's kinda right right now

[CompleteXen]

Originally Posted by 2js1493

Starting to realize standalone is the only option. Question is do you guys think I can get away with a piggyback module or do i need to go full standalone. Money's kinda right right now

Look up to one of my previous posts. Honda or Evo AEM EMS v1. Can be found on eBay for pretty cheap roughly $300-400. Their are guides online on how to convert them or you can send it my way at Powerdynamix to convert it for you for $100. If money's tight you'd be better off doing it yourself though as it's pretty simple. If you go that route you need a junkyard Mitsubishi or Honda harness depending on the ecu you got and then just mix and match the wires for the 2j harness to the junkyard harness.

A piggyback is not something I'd ever recommend, don't go FIC, don't go Emanage, go standalone. If money's tight, stop spending money on the car, be patient and save.