Help Help!!! Runs Rough!!!

Post by **elwesso** » Tue Dec 30, 2003 9:12 am

Got the plenum back on, and everything hooked up, and now it shakes like none other.... I dont think its an injector because it would throw a CEL... Not there.... I dont think there is a vacuum leak, because I went slow and stuff like that......

ANY SUGGESTIONS?

Post by **ChiQ45** » Tue Dec 30, 2003 9:12 am

dam it i was dreadin you posting something like this..hope its an easy fix wes

Post by **elwesso** » Tue Dec 30, 2003 9:12 am

Yes I did both of those.... Donuts are brand new (I could only find 7/8 of the metal rings that go inside the plenum gaskets)......

Ill check on a vacuum leak, i think i heard something under there, but I dont see how I could have left something undone....

Hopefully if I find something it will be easy, because I checked the tough hoses and the big ones and I couldnt find anything...

Also, I didnt tighten the EGR all the way on the manifold (Not sure how im gonna do that, no room)....

I have my cell on, 765-621-8336

Post by **DAEDALUS** » Tue Dec 30, 2003 9:12 am

Sorry, I deleted my post because I realized the symptoms are not the same. Go ahead and check with the WD-40 mist, but if it feels like it's missing a cylinder, then I would suspect a plug's not firing. Coil maybe? Did you remove the plugs too?

Post by **PalmerWMD** » Tue Dec 30, 2003 9:12 am

Guru's:

Wes is a good friend of the site, a teenager who has attacked a tough job with the determination of a much older man.

He deserves all the support we can humanly give him.

If a lenghty long distance call is neccessary to help him, I will glady send a MO ro reimburse callers.

Fred..

Post by **elwesso** » Tue Dec 30, 2003 9:12 am

Thanks Fred, I really appreciate your support.... Man I love this place......

I didnt remove the plugs, but my no 8 coil doesnt have any mounting bolts holding it on.... Ive been running it like this for a long time (since i replaced the plugs last time) and no problems....

It does feel like a cylinder miss, kinda...

I'll go back over to the shop and double check all of my electrical connections and other things and see if it changes.....

Are there any ways I can differentiate between a vacuum leak and a miss??? I would assume a vacuum leak woulds make the RPMS fluctuate a lot and a miss would just make it shake, but RPMs are steady......

Post by **elwesso** » Tue Dec 30, 2003 9:12 am

YES!!! :fruit :fruit

I AM AN IDIOT!!!!! I FORGOT TO PLUG BACK IN MY CONECTORS ON THE PASSENGER SIDE IGNITOR PACK!!! IT LIVES!!!!!!

But, i have another thing... When i started it, it raced up to 2000 rpms and there is a noise from the front middle part of the engine... Sounds like a groaning, very similar to when there was air in my PS lines!! Water pump?? Because I had to drain coolant???

Post by **elwesso** » Tue Dec 30, 2003 9:12 am

I drove it around, runs GREAT!! I can finally do my much coveted burnout!!! WOOHOO!!!

New concern.... When I first started it up, I got a TRANSMISSION MALFUNCTION... The tranny also felt sorta weird (sloppy, and not shifting at the right times).. It also does not come out of fast idle.... I tried adjusting the IAC and it doesnt lower the idle at all... Its screwed in like 5-6 turns, and idles at 1250.... I did a preliminary checks and didnt come up with anyhting.....

I have unhooked the battery and will see if that does anything.... but any ideas???

Post by **911/Q45** » Tue Dec 30, 2003 9:12 am

That fast idle sounds like a vacuum leak, did you triple check that all those silly hoses are connected? I'd guess an electrical connector for the trans got bumped off during you O2 sensor and EGR wrestling.

Post by **elwesso** » Tue Dec 30, 2003 9:12 am

I forgot to mention... The transmission malfunction thing only stays on for a few seconds... It goes off as soon as I put it in gear...

Ill look into another vacuum leak... But at least the car is driveable and smooth.....

Post by **DAEDALUS** » Tue Dec 30, 2003 9:12 am

I just tried calling and left a message. Been sleeping most of the day with a cold. Try jiggling the 3 connectors just inboard of the TB.

Post by **nuQ** » Tue Dec 30, 2003 9:12 am

wes first off, CONGRATULATIONS on a job well done. I was thinking about you these last few days. how many ratchets did you throw!!!!LOL was wondering wes,,,did you change the knock sensors and/or the O2 sensors?????? i guess you can tell a big difference already. congrats again, jeff

Post by **elwesso** » Tue Dec 30, 2003 9:12 am

Robert.. Im very sorry I didnt have my phone on, I put it on charge and I didnt realize it was off.... I would have liked to talk to you....

I plugged the battery back, and I didnt get the message, feels just like normal...

I must say, the power is MUCH different.... Very noticeable....

I will look into my vacuum leak tomorrow. Its somewhere around the EGR area, I think....

Post by **elwesso** » Tue Dec 30, 2003 9:12 am

Jeff.... I replaced the KS, and like I said in the above post I can tell a difference.... It feels somewhat stronger, but I dont have a complete opinion.... I have 89 octane in the tank, and I still have a vacuum leak..... I will let you know once both are fixed....

And when I went to replace the KS and those stupid coolant hoses, I threw a set of pliers on the ground about 10 times.... I still get terrible flashbacks from that....

I have my write up pretty much done, and will post ASAP....

Post by **Q451990** » Tue Dec 30, 2003 9:12 am

elwesso wrote:And when I went to replace the KS and those stupid coolant hoses, I threw a set of pliers on the ground about 10 times

I think that's part of the textbook method! When I replaced those I actually called the tech at my local dealership and asked him if I needed to remove runners, or what exactly needed to be done. After he stopped laughing, he said "we always start with kicking the $HlT of of the car..."

You've made it through one of the toughest repairs on the Q. Good luck with that idle problem... I'd suspect a vacuum leak as well.

Check the AT section of the FSM for the test method to pull codes on the "AT MALFUNCTION" message.

Heath

Post by **Q45tech** » Tue Dec 30, 2003 9:12 am

Finding vacuum leaks can be done electronically with a digital sensitive vacuum/pressure transducer and an oscilloscope synced to #1. [or any firing postion to keep waveform locked to rpm]

The scope will display 8 individual [equal?] dips/ rises in vacuum --- one for each cylinder, same with MAF voltage, same with pressure pulses on the fuel pressure regulator [isolated from plenum vacuum].Just like compression testing requires every cylinder be the same within 10% [14 psi]..........all vacuum reading should be the same.

I am refining a method to measure the AIR pressure at the oil filler port..........to measure blow by [poor piston compression rings at start up] and how this changes as the rings expand with warm up.A perfect [ringed] engine would have no pressure [outward flow of air]with the oil cap off!.......also test PCV system.

A vacuum gauge teed to the vacuum line feeding the fuel pressure regulator should read 18" [+- 0.5"] HG at hot idle.

Post by **elwesso** » Tue Dec 30, 2003 9:12 am

I posted this in another thread of mine in the INFINITI GENERAL section, under "anyone wanna come help"

I checked the FSM for HIGH IDLE AFTER WARM UP (diagnostic procedure 33. EF-EC 176) and it talks about unplugging the MAF, and then starting and running the engine at 2000RPM for 30 seconds, and if the engine speed drops then its an air leak....

Quote » 1. Disconnect Mass Air Flow meter harness connectors 2. After starting and running the engine at 2000 RPM for at least 30 seconds, does the engine speed drop? --------> Discover air leak and repair. [/quote]Like I said earlier, I unplugged the battery for an hour or so, and the tranny is back to normal... Maybe its not used to having this mad power yet....

Now, just to get some 93 octane in it!! (running 89, i ran 89 when I had the old KS).....

Once it warms up a bit, I will check into the vacuum leak..... If I dont figure it out reasonably, I may just leave it and take it to a dealer sometime (or maybe to T3

)

Post by **nuQ** » Tue Dec 30, 2003 9:12 am

i've decided to take my Q to vanmeter auto for the plenum job, just think without a garage of my own, and very limited time, out of my league right now. talked to keith vanmeter the other day (BTW said a fellow NICO member was bringing their car in for work recommended by me???? anyone, anyone?), told him i had a job for him that he probably wouldn't like to hear. when i told him what it was, he laughed and said no problem. said he's done a bunch of them when he worked at the dealership. told me the labor hours wouldn't be that bad (3-4??????), can this be possible????? he said he thought i was going to say a tranny replacement--his least favorite!!LOL

Post by **elwesso** » Tue Dec 30, 2003 9:12 am

I dont think that will include ALL hose replacement (There are a few that I cant see happening without the runners being removed, and you gotta take out the fuel rail for that), KS replacement (terrible), and rocker covers......

Post by **Infinitiguy19** » Thu Sep 24, 2009 10:51 am

Q45tech wrote:I am refining a method to measure the AIR pressure at the oil filler port..........to measure blow by [poor piston compression rings at start up] and how this changes as the rings expand with warm up.A perfect [ringed] engine would have no pressure [outward flow of air]with the oil cap off!.......also test PCV system.

Have you found a good method for measuring air pressure from the oil fill hole?

Post by **Q45tech** » Sun Sep 27, 2009 6:11 am

Just drill a hole thru oil filler cap and install a metal pipe [tiny] and reverse manometers to measure pressure. +27.7" H2O = +1.0 psi

You won't find much but a good method to check rings and pcv cleanliness.

Again a digital pressure sensor/oscilloscope lets you look at the 8 different pressure pulses.

Help Help!!! Runs Rough!!!

Help Help!!! Runs Rough!!!

Re: (Q45tech)

Re: (Paul Wall)

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