FGY33 Plenum Removal, *Finally, a walkthrough for the 4.1*

[maxnix]

Time for a NICO tune up!

WOT rules.

I don't think any of us has only done it one time the first time.

[fcdrifter20]

i kno this is an old thread, but thany u farfetched i was able to use ur method thnx to my tiny hands. save me lots of time and money

[paranoidjack]

It really amazes me that you guys did that. Seriously - anyone else find that damned near impossible???????

[bullittandy]

Remember that scene in star Wars when Obi wan tells Luke to lower the blast shield and then practice with his light saber

You just have to believe that you can do it and then go by feel.

[omarb45]

Are you going to re-install your vetech and tv sitting on table too/

[mizuno7006]

My 98 Q started running very rough on Thursday so I ran by Advanced Auto for a free OBD II scan. It told me both the left and right bank "KNOCK SENSORS" (KS) were tango uniform. I came home and searched this forum and decided I needed to do the deed. I purchased two OEM KSs from the dealer for $130 a piece. (didn't want to risk having two piece of s__t KSs from ebay)

Paranoidjack and FarFetched had two excellent methods to replace the left and right bank "KNOCK SENSORS". Being a retired aviator...read "get in the fight and get 'er done", I elected to go with Farfetched's method first.

Removed the fan, alternator, thermostat/radiator hose and the cables from the throttle body (passenger side) and got a visual on the two KSs. Was able to squeeze my hand into the cavity with a 1/4" drive 12mm socket.

Removed in about 10 minutes...now here came the a_s pain....could not get the plugs disconnected from the KSs. Maybe I didn't read enough of the threads, but found out there is a brass retaining clip holding the KS to the connector. Look at Paranoidjacks KSs and you'll see it.

Well there was no way....no way in h_ll I was going to get those clips off in the cavity, so I just about gave up.

Then the area where I removed part of the cables from the throttle body (located directly behind the alternator) [I had some divine intervention....] I saw the KS cable heading back to the firewall...I wondered if I could reach the KS from the back of the engine....

well wouldn't you know....I reached into the back of the plenum and started pulling on the harness and guess what......I was able to pull both KSs out and disconnect them using a small screwdriver. I clamped the new ones into place and stuck them back into the general location of their mounts.

Now, here is the part where patience is needed. The passenger side was screwed down pretty easy, but the driver's side was near impossible. There was no way I could reach my hand in the cavity and put the bolt into the KS due to a cross pipe in front of the mount.

So after 30 minutes of bending over, I pulled the KS back out the back, put the bolt into the KS, put some tape on the bolt to hold it and pushed it back into position. This time I was able to carefully remove the tape and place the KS with bolt into the mount and attach!

My car runs great and I am glad I did it. So the bottom line...don't give up...and read all the tricks that have been done and you'll have your Q running great again. My hands are all torn the f__k up, but hey, remember "pain is weakness leaving the body."

Thanks again for the great pictures paranoidjack...I did clean the butterfly valve in the throttlebody which was dirtier than an LBFM from the PI.

PS. The money I saved in labor, is now going to get me some new 18" wheels for the Q....Sweet!

[Haitian_King]

Congrats on that bro!

[Marshall206]

This is awsome, best thread I have found on here. Im going to tackle this one very soon, I very badly need to replace my gaskets as well.

I was waiting for this, now I can restore my q, so perfect you even have the same year.

ME: bad k/s, leaky valve cover gasket, bad coil or 2 or 8, dirty engine, and prob got a bad fuel hose or 2

This is a good project to start on, then I can do coils when I have more money.

[Marshall206]

how much was the job in parts? including k/s

[paranoidjack]

[maxnix]

The whole problem doing it by removing only the alternator only way is how do your get the correct torque on the KS, which is critical to their operation? Then there is that little 10mm nut that locates the harness on the block.

Not to mention you never see all the other stuff that needs to be corrected, like the EGR tube in the plenum and the IAC valve, EGR valve, lower runners, plenum itself?

Like most shortcuts, you are only fooling yoursel, not the engine.

[mizuno7006]

The two knock sensors cost ~ $130 each...so $260 was the total bill. When you remove the alternator and throttle body cables, you can do a pretty good visual inspection of your engine...and boy was plenum and under the plenun dirty. I used my compressor to blow out the dirt.

Also one note that I forgot on the original thread...when you remove the aluminum coolant pipe, expect to get some anti-freeze to collect on the top of the engine next to the knock sensors. I had just stuffed a couple of paper towels in the remaining pipe to stop the dripping and used my wet vac to clean the anti-freeze that pooled.

My main reason that I didn't want to remove the plenum is because I didn't have any of the parts/gaskets on hand and I needed to get the car running since it is my daily whip. I did check my plugs and not a drop of oil leaking into the sparkplug holes; hence my valve cover gaskets still doing their job.

[maxnix]

I did check my plugs and not a drop of oil leaking into the sparkplug holes; hence my valve cover gaskets still doing their job.

VC gaskets leak on the low side above the headers first. By the time they start to leak into the spark plug holes, it is way too late.

[qbert45]

DAMN, that throttle body was DIRTY!

[maxnix]

DAMN, that throttle body was DIRTY!

Now think about the plenum and lower runners downstream after it and the EGR tube inside the plenum. Think they are any cleaner?

[Marshall206]

ok quick clarification needed,

are you saying my misfiring, possible bad coil, s***ty running car could be oil leaking from my vc gasket and into my spark plugs?

I think there is a good chance that this is the main prob with my car,

TCS Slip coming on and staying on from what ive been told = bad k/s or dirty MAF/bad connection

misfiring from what ive been told = most likey bad coil

but possibly those are bad but the oil leak has caused the spark plugs to not fire?

seems like I should replace all of these: k/s + harness, coils, and gaskets

ANY thing else I should do while im in there?? other than a lot of cleaning

going to start this project in about a week so just want to make sure

[paranoidjack]

send your injectors to Deutscheworks and let them rehab them. Cheap as could be and WELL WORTH IT.

I put my crappy, terrible, broken pintle-cap-having injectors in TWICE already. Can't wait to pull them this summer and send them out.

[maxnix]

Stress test the battery and the alternator. before you take it all apart so you know if you have to replace those. If one or the other is bad, it will take out the good component in short order.

[Skibane]

Jack, your scanned receipts appear to show suspension components, rather than any parts related to this job. Do you have another image that shows the correct parts?

[paranoidjack]

Jack, your scanned receipts appear to show suspension components, rather than any parts related to this job. Do you have another image that shows the correct parts?

WELL Skibane that took forever!

Apparently, since the changeover, many or all of [IMG] tags didn't come through, and other formatting as well. This problem ONLY surfaced once posts are EDITED.

I got the CORRECT paperwork from my file cabinet, scanned it, and as soon as I hit "edit" on this post, the whole thing went to heck and lost all images and formatting.

I spent a few hours this afternoon re-organizing the post and uploading that scanned receipt. I probably wouldn't have gone to the trouble, but since making this post I have received MANY emails from all over the world from people either thanking me or asking questions, so clearly it is of use to the public.

Anyway, rant over, new stuff uploaded and all fixed.

[enmjae]

mine just died today as well...what an awesome write up~!!

[maxnix]

Died?

RIP.

[paranoidjack]

mine just died today as well...what an awesome write up~!!

What?! You were just about to do grills and emblems and your engine dies?! Booooo what happened???

[maxnix]

mine just died today as well...what an awesome write up~!!

What?! You were just about to do grills and emblems and your engine dies?! Booooo what happened???

I am guessing deferred maintenance.

[D-Town Q]

I need some help, I am going to have both my KS replaced by a mechanic since I am not mechanicaly inclined whatsoever. I read through this walkthrough but was unable to see the receipt for the parts and unable to see any of the in progress pics. Went to the Mechanic today and he said get the Intake gasket and the Plenum gasket. I can't find part numbers and the "manifold gasket" are listed as upper ($4), lower ($39), and manifold gasket ($47). Are any of these the correct ones and are those the only ones I should hand over to him?
CEL light w code P0330 brought all this on.
(also going to have the o2 sensor replaced due to code P0420) All info is appreciated.

[Mopar]

He is right. Those gaskets are the bare minimum that needs to be changed. You can not put the old ones on. I would add the throttle body gasket to that list also.

However, if you have time, maybe you can get the parts from the mechanic and clean them yourself. Trust me, you will want to do this as the build up of crap is clogging your intake system. At the very least, you need to take out and clean the hard EGR tube in the manifold. Which will require you to get 3 extra egr gaskets.

[lamsv]

Just finished replacing my knock sensors. By far, the most frustrating and time consuming replacement I have ever done. I did not remove the intake manifold. I used the alternative method of removing the alternator, coolant pipe, snaking the knock sensors to the rear of the engine, replacing them, and, by the grace of God himself, installing them back in their location. It was a task I had been dreading for weeks, and I am most definitely happy it is over.

As far as the car running better? I can't really tell. Seems to be a little less sluggish. But, I did not clean the intake/EGR/TB/etc. Still. I'm sure it will be worth it in the long run.

[carnal_c30]

anyone have the part # for the coolant hose that runs under the valley? I'll be doing this job soon and can't recognize the hose in the parts diagram.

Thanks!

[lamsv]

I just took the old hose to a parts store, and had them cut me a new piece from their stock of radiator hoses.

[carnal_c30]

sounds good! Thats not too hard to do