1JZ running rough!

[CanadianLurch]

Hello everyone, well i got some crappy news. I went for a drive last night and everything seemed great on my car. I went out this morning and started it to take a movie back and it seemed to be idleing very low. And when i start to drive the car doesnt drive right. There is a noticeable power loss, and when i punched the gas to see what was up I wouldnt get full boost. Any ideas? the car has been running great for the last week or so which leaves me very confused? And to top it all off Im visiting my parents in Calgary which leaves me kinda stranded as I dont want to drive it home...Has anyone had this problem? im hoping i didnt blow something up as I havent been driving it that hard!

Thanks

Steve

 

[CanadianLurch]

I took a look at the vaccum hoses and noticed my MAP sensor may look a little rough. Im pretty sure it is not supposed to be melted like this. Can anyone shed some light?

 

[garagefujimoto]

Was it mounted in a hot area?
You need a new sensor ... is it is leaking?
If it leaks, it's no better than having it unplugged.

 

[CanadianLurch]

it doesnt seem to leak. it was mounted by the brake booster and the plastic clamp that was attaching it to the line didnt melt....it just looks like the sensor did.

 

[johnd]

Check for codes, 31 is the map.

 

[CanadianLurch]

I didnt get any codes when I tried the paperclip in the diagnostics box. Someone had also said that it may be a fried ecu? I checked inside of the box and the capacitors LOOK fine. Does anyone know if they can fail without "exploding" the black shit all over the motherboard?

 

[Shima]

i had this issue with my 1jz turned out my plugs were fried. changed the plugs and its spot on now. boosts fine. its always the smallest things that get us bad.

 

[Frankenstien]

Yes, they can fail without exploding.

 

[Frankenstien]

Also, bad plugs as stated above will cause this. What's your wideband read?

 

[CanadianLurch]

I put brand spankin new spark plugs NGK platinum (they were sold out of irridium) (im assuming those are the plugs ur talking about) when i did the transplant so im hoping that isnt the issue...
Looks like im shipping the ecu off to DM tomorrow then. I hope this gets me back on the road, as I have had a 3 day "teaser" run and now im addicted to 1JZ. Is there any support groups for that.....i know im past step 1 (admitting you have a problem) lol.

thanks a lot for all the help guys I really appreciate you taking the time to answer my questions so promptly!
Steve

 

[CanadianLurch]

And also I dont have a wideband gauge so im not really sure what my A/F is. Is that going to be an issue diagnosing my problem?

 

[garagefujimoto]

What part number of plug did you install?
Is the problem any better?

 

[Frankenstien]

A wideband will give you an idea what's happening in your engine. FYI, coppers are best for a boosted engine. Platinums are ok though, did you gap them correctly?

 

[CanadianLurch]

Honestly i didnt install them but my buddy that did the work on them I believe gapped them correctly. I have put 1000+ km on my new spark plugs with no issues until this morning. A couple others suggested my ecu may be fried (because my exhaust smells like gasoline)
here is what my buddy annyingrob had to say:
anadianLurch: For the 1JZ, what has happened is one of your injector drivers has died, and it holding two of the injectors open, causing it to run super rich. So rich, that it can't ignite the air/fuel in two cylinders.

If you need to get it back to lethbridge, unplug the bad injectors, and drive it on 4 cylinders. If you drive it with them plugged in, you will go through a ton of gas. Alternatively, snip the white wire running to the injectors, and jumper it to another working injector.

After that, find someone to fix your ECU, or get a new one
FYI: I got a ride home and will be driving my truck until the problem is fixed. So for now the sup' is in Calgary at my folks house

If this does not fix the problem I think my next step will be new spark plugs. as for new ones i shouldnt use irridium? (can i get ngk copper plugs?)

Thanks again

Steve

 

[CanadianLurch]

What part number of plug did you install?
Is the problem any better?

i have not changed spark plugs since problem arose. I put brand new ones in when i did the swap.
maybe tomorrow i will check the gap on the plugs before I send my ecu away just in case (possibly even get new copper ones).

 

[Frankenstien]

^ Rob's diagnosis sounds reasonable, wouldn't surprise me at all if that were the case. I just like starting at the simple things, like plugs. But if yours are fine, then I wouldn't worry about it except getting new ones as the ones in the rich cylinders will be fouled.

Try taking a look at your plugs asap, they will tell you a lot about what is happening. Until then, I wouldn't go around saying "it's this, no, it's this, or maybe this is what's wrong." Pics are worth 1000 words, post some up.

And yes, iridiums are good plugs, just not the best for a boosted application.

 

[CanadianLurch]

ok thanks a lot, i will definatly get some pics. i did mention above that tomorro when i get home im going to check the plugs and the gaps first. and also i will get 6 new copper plugs if i have to replace 2 i may as well switch them all to copper now! i am not in Calgary right now so I cant do anything to it until tomorrow when I drive back up there with my truck!

 

[Shima]

plugs i use are ngk bkr7e

cheap and they love the boost

but check the plugs before snipping injector wiring scary dude. :cry:

 

[CanadianLurch]

I didnt snip the plugs. as i have said before i am not driving the car until its fixed and running proper. I have a DD that will get me by just fine until then. I will be changing all the plugs when I get the ecu back as i want to get it tested and redone anyways after the reading ive been doing. I think a combination of the above should fix my problem. i will update in a week to let you guys know whats up. Thanks for the help

 

[CanadianLurch]

Well i replaced the spark plugs and she fired up just like normal. The old spark plugs were blackened which leads me to believe they were soaked by the gas (I could smell gas on the first plug especially). The car seems to run fine but when I give it gas in neutral it want to sputter out around 2-3000 rpms (the car did this from day 1). If the car is in gear it will drive normally through this range (boost and everything) this only happens when i have the clutch in or am in neutral. Im starting to believe that there is something else wrong, 2 of the coilpacks had hairline cracks (didnt look to be major and not sure if this would be problem as the car will pull hard to 7000 it just wont rev in neutral between 2-3000!?
Does this sound like it still may be a faulty ecu? or does anyone have some other suggestions to try? The exhaust also no longer smells of gas but I have a feeling these plugs are only going to last me another 1000k

Thanks for the help