Pleae keep it light and friendly guys, after all we're only here to try and help each other, we're all in the family as it were with a shared interest.

Thank you all for your many posts, trying to help fellow enthusiasts, long may it continue.

Thanks

 

Don, I don't think anyone hears doubts what you have had to say. I was simply pointing out a couple of areas that you hadn't mentioned.

I'm also happy for you to get "the last word in" so to speak so what I'm about to write is more for the benefit of those that would like to be made aware of things that they may have overlooked or not considered.

Re the CVS... I would think that everyone here agrees that the Air Intake is subject to a build up of sludge which in turn affects performance of the engine and can contaminate the TPS. Where do you think that this sludge comes from? It certainly doesn't originate from the air box unless of course you have installed an oiled filter and over oiled it. Also against common belief, the air is not drawn against the laws of physics. I.e. from the intake manifold backwards to the air box. The Air only flows in one direction under relative vacuum from the air box, though the intake, though the throttle body and into the Intake Manifold. Yes, examination of the hoses in this system is imperative to ensuring that the system remains in a relatively sealed and clean state and also free of the dreaded sludge.

Pause for a second and think about it. Air is drawn from the Air Box. Depending on the state of your air filter this air is relatively "clean". Recirculated air is also drawn through the Intake via the Crankcase Ventilation System. This air is not "clean" as it recycled through the engine back to the Intake via the Crankcase Ventilation Hose. This is the CVS hose that enters on top of the Intake Elbow via the Heating Element. It is from this hose that the sludge originates. Cleaning out or replacement of this hose will reduce/eliminate the resultant sludge from entering the elbow of the intake. Replacement of this hose saves the headache of trying to clean it out with a solvent which will only serve to deteriorate this hose in the long term or having the hose break when trying to remove it for cleaning. Having a spare one on hand will save wasted time trying to source a new one in the event that it does break. Problem Solved!

The problem is not resolved when people overlook this hose and go straight to the TPS without resolving the cause of the sludge in the first place. A clean CVS together with regular clean oil and filter is a good cost effective preventative here.

If you don't believe me then may I also draw your attention to Chapter 6, section 8 of the Haynes Manual together with Drawing 8.1 which shows the schematic of the CVS.

Re the transmission... Maybe you can explain to everyone why there is a T.S.B from Jaguar which advises against revving the engine above 1000 rpm whilst in Park? Having rebuilt the ZF4HP22 transmission (myself) I am fully aware of the reason for this which is why it is important to renew the fluid at recommended service intervals. Many an engine stall problem can be traced back to issues with the transmission and in particular the torque converter, or for those familiar with the ZF4HP22 and the T.S.B., the problem which arises with the shaft seal in the "A" pack clutch. Clean fluid can often overcome any issues here, or at the very least, prevent issues from occurring.

As Red is relatively "new" to the world of Jaguar xj40's then it is only responsible to suggest that whilst he was in the process of "servicing" his engine (see original title of the thread) that he also consider servicing other items including the transmission which is something that is often overlooked.

I can't see an issue with spending a few dollars extra on "consumables" or a bit of extra time pulling a spark plug or examining a component as a preventative maintenance strategy? After all, some of these may be directly related to the initial topic of this thread and the only way you can rule them in or out with any certainty is of course to attend to them!

 

hey fellas..... I am sorry if I have caused some distress here on the forum.... this certainly was not my intention...
I posted for suggestions and that's what I have received.... I am happy with all the responses posted as they are all worth investigating....

It is true she has done 333000+ kms so things like timing may be slack and in need of replacement or repair..... I am not familiar with her history service as there was not a lot told to me when I bought her.....
I do however have a long list of things that have been done, roughly totaling about $4000Au included in the owners manual cover.

It is also true my car does need her well over scheduled service of fluids and the like... I know this and have every intention or replacing them all.

As suggested by Don.... I have deliberately put this off for the time being as I wanted to get her running smoothly before doing the regular maintenance.

where as I totally agree with the suggestion of starting with the serviceable parts, I figure that if (worse case scenario) I have to strip the motor and replace timing chains and guides..... it would be more appropriate to wait for fluid service until that is done.

I have stated I really am not familiar with electronic aided vehicles.... in my 40 odd years of driving I have always owned and worked on naturally aspirated, non computerized cars. but my instincts pointed me in the direction of air intake obstructions or incorrect throttle body positioning as causing the rich mixture and rough idle.

I do not pretend to know, this is why I asked in the first place.....
and I repeat.... I do appreciate "ALL" the advice offered on here and will sum them up and attempt the ones I feel are most likely (in my opinion) to be causing the problems and then systematically go through the possible causes until I isolate it or them.

 

And for those that have supported my input, Thank you.

I'm not for a moment suggesting that I am correct in diagnosing the Issue(s) that Red and others are experiencing. I am merely pointing out other possible areas of concern that Red and others may have overlooked.

 

Hi Jagfix38,

I hope we didn't get off on the wrong foot, and I certainly don't need to "get the last word in." Hopefully the last word will be Red's, when he reports that he has successfully sorted his issues. I'm sure that's the goal we're all working toward.

Red, for your sake, I don't want your thread to be hijacked or to go too far afield, but I do believe that accuracy is important to save you time and money. If I make any incorrect statements I want to be corrected. Similarly, we shouldn't leave any potentially-confusing statements un-clarified, both for your sake now as well as for future readers of this thread who may have symptoms similar to yours.


Jagfix38, I think you and I agree that the source of most of the TPS contamination is the crankcase ventilation or engine breathing system, which draws oily vapors from the crankcase and cam cover and delivers them right into the intake elbow ahead of the throttle body (see the caption of photo number 2 in my photo album on cleaning the TPS where I describe this process within the Jag-Lovers limit of 300-characters including spaces... :-).


Just for clarity, in case Red wants to look up this hose or any others, Haynes uses the generic terminology Crankcase Ventilation System, but the Jaguar Service Manuals and parts diagrams mostly use the term Engine Breathing System (I found only one reference to the "Crankcase Control System"). The hoses are generally called Engine Breather hoses or by more specific names. For example, the Y-hose Haynes calls the CVS hose is called the "Filler Pipe to Restrictor Hose" in the Jaguar parts diagram, which can be easily found at jaguarclassicparts.com.


Cleaning the hose is certainly worthwhile, but as you and I have previously agreed, the source of the sludge is not actually the hose itself, but the oil and contaminants in the vapors that are continuously drawn from the crankcase and cam cover into the throttle body whenever the engine is running. Through periodic maintenance we can reduce the effects of sludge accumulation, but due to the design of the system we can never actually solve the problem. And since the sludge in the hose is less likely to cause serious engine performance issues compared to the sludge that makes its way into the TPS, it makes sense that we more often see recommendations to clean the TPS than to clean the hose, since cleaning the TPS is more likely to significantly improve engine performance. But you're absolutely correct that it's a good idea to periodically clean the sludge from the insides of the entire air intake and engine breathing system, and to renew hardened or cracked hoses.


The TSB explains itself, warning of a risk of internal transmission damage if the engine is run above 2,000 rpm or run at high speeds for prolonged periods while in Park or Neutral, but since there is no mention of start-up rattle, rough and erratic idle or rich running, I'm still unsure of its relevance to Red's issues:



That is a truly impressive accomplishment, Jagfix38! I have a friend on another forum who may be facing the need to rebuild his transmission due to a harsh 1-2 shift (he's going to try a thorough fluid and filter change first, but he did that a couple of years ago and it didn't improve the situation). Do you have photos of the process that might be helpful to him? As far as I know, no one has posted a photo-tutorial on the ZF XJ40 transmission rebuild process (not that most of us are brave enough to tackle it like you did).


Here's page 1 of a TSB you may be referring to. It does refer to the stalling due to low transmission fluid that I mentioned in an earlier post, and low transmission fluid is also the first item to check on the Engine Stalling troubleshooting flowchart in the XJ40 Diagnostic manuals. But Red isn't complaining of stalling, and there is no mention in this TSB of rough and erratic idle or rich running.... So can we agree that Red can attach a lower priority to the transmission while he searches for more likely causes of his current issues?




While I'm digging through my TSB folder, here's the first page of one of the TSBs Jaguar issued about rattle after start-up that may be helpful to Red. I recall that there were earlier TSBs on this same issue, but this is the one I have saved:






Red, all of these TSBs are available in the TSB section of this forum at the link below, courtesy of Bob Gauff (Motorcarman), uploaded by Translator, and given sticky status by JimC64:

https://www.jaguarforums.com/forum/x...t-s-b-s-27319/

Cheers,

Don

 

Hi Michael,

First of all, thanks for reading my posts. I read yours too. I regret that you and Jagfix38 feel that I “quibble a lot,” but I’ve learned the hard way that for someone whose Jaguar is malfunctioning, the more precise the suggestions received the more likely a prompt resolution will be achieved with the least expense. General advice about routine maintenance is fine, but offers little joy to someone whose problem most likely falls outside the realm of the typical tuneup.

I’m certainly no expert myself, but when you own and personally maintain the same car for 16 years (and a similar one for 4 years prior to that), and you spend time searching the forums and references for solutions to the inevitable and numerous issues common to Jaguars, you tend to learn a thing or two, and in my case, I haven't learned them on my own. Beginning with our first XJ40 (an ’88 purchased in ’94), the XJ40 experts at the Jag-Lovers forum literally taught me how to maintain and repair our Jags. Over the years they have saved me hundreds, if not thousands of hours, and thousands, if not tens of thousands of dollars. Along the way, I began to apply my experience in photography and professional writing to create photo-tutorials to help “pay forward” all the generous help I have received from those more knowledgeable owner-mechanics who have mentored and trained me.

The Jaguar Forums are continuing that fine tradition. As someone recently posted, "To share knowledge is to save money." As much as I've learned, I still don't know it all. You know things I don't yet know. Rob, Larry and Jagfix38 know things that neither you nor I know. It's our complementary, collective knowledge that makes these forums so incredibly invaluable to all of us.

I’ve found myself here at the Jaguar Forums because the X350 community is larger and more knowledgeable than the one at Jag-Lovers, and with our '04 XJR I’m back at the bottom of the learning curve again, trying to soak up all the knowledge and experience represented here.


That is certainly a worthwhile goal. The challenge we face is that some symptoms may be caused by more than one fault. Rough and erratic idle and rich running are perfect examples, as evidenced by the wide array of replies Red received. Offering Red one specific solution and procedure would have a low probability of success, since there are so many other possibilities he may also have to investigate.

Mentioning a “quicker less expensive procedure” is great, when we know what the actual cause of the problem is, but at present we don’t know the specific cause or causes of Red’s issues. He’s going to have to do the diagnostic work, and all we can do is suggest the components and systems he should investigate that have the highest probability of causing his specific problems. That may seem like a lot of unnecessary theory to you, but it's the best we've got until Red acquires additional real-world data.

Your opinion may be that I’ve “overdone” the work on our car and could have maintained it with less effort and expense, but since our '93 is quickly approaching 200K miles and our son is driving it at college 6-1/2 hours away, I’ve naturally wanted to do everything possible to ensure that it’s the most reliable daily driver possible. I long ago adopted the policy of servicing entire systems rather than one faulty part, replacing parts preemptively whenever I have to remove them to access something else that has failed, under the assumption that if one part of the system has already failed, the other parts are going to fail sooner rather than later. Overkill? Wasted time and expense? Every owner has to make those decisions personally, and what I've decided for our car may not be best for yours. And when I later decide I would have done something differently, such as the hindsight perspective that installing a professionally-rebuilt differential would probably have been more prudent than rebuilding our diff myself, I say so.

No one who actually knows me would ever accuse me of having too much time on my hands (in Tennessee it's currently 1:30 am Thursday and my day started at 6:10 am Wednesday). I burn my candle at all three ends and have to do without sleep to spend time on things I enjoy, like our Jaguars. So I follow the dictum, “If you don’t have time to do it right the first time, when will you have time to do it again?”


Since I know several Jaguar owner-mechanics in Australia (and New Zealand, Singapore and Hong Kong), some of whom are even more meticulous in maintaining their Jags than I am, and from whom I have learned much over the years, I’m not sure what you mean by the phrase, "...as we do in Australia." I really do want to know the simplest and best ways of maintaining our cars, so I was serious when I asked you for a link to your post about the TPS. Who knows, maybe I’ll agree with you that the best way is “…as you do in Australia.”

Cheers,

Don

 

Some words of wisdom, I especially like the part in bold......

We are all here essentially with the same aim in mind although we may choose the approach differently from others.

By helping each other we can hopefully learn new things and the pay it forward helping others, and so the cycle continues....

 

update:
I pulled out the air cleaner box, the MAF, elbow and the attached breather pipes today and gave them a thorough cleanout in a bit of petrol (gasoline).

There was a fair bit of oily sludge in the elbow especially.... I took the MAF unit apart completely and also thoroughly cleaned that out too.

Looked at removing the throttle body to clean it also, I may be wrong but it looks like I need to remove the manifolds to get to it..... there are 2 bolts at each top corner and 2 at each bottom corner.... I really don't think I can get into them with my sockets.

The other option I could see was to remove all the top assembly (throttle controls) which would possibly clear the way to the top ones.... and then climb under the car and remove the oil filter to possibly get to the bottom ones.

If I am wrong on this point and there is an easier way, I would appreciate instruction.
step by step photos of removal would be good

 

You can remove those four bolts on throttle body with a socket set, Bob, you just need a u-joint and a small extension. Earlier in this thread (post #3) I included a link to the photos and (partial) how-to of removing & cleaning mine up. There's a tip or two there too.

Larry

 

Ok thanks Larry will go back over it and check out the links


Ok just looked through your pics and also the others posted on Jag-Lovers and from what I can see it seems pretty straight forward.

I did however note some subtle differences... I don't know if maybe it is different engines ie:4.0ltr as opposed to my 3.6ltr the pics look like there is actually slightly more clearance than mine has... this may just be an optical illusion from photos...

I also noticed my breather hoses are not quite the same.... firstly I do not seem to have the inline breather heater on the rear hose...
and on the front breather hose on the elbow on mine there is like a hooked pipe that travels down (vertical) to meet a do-hickey under it. almost looks like some kind of solenoid canister thing. (getting real technical here, hope you can follow) lol

other than that it seems pretty much the same

I guess that will be the next thing I tackle.
My throttle body seemed pretty clean from the inlet side, but I can only imagine the other side of the butterfly will be coated.
even if it's not, a good preventative service will not hurt.

 

Red,

In regards to removing the throttle body, you may want to give this thread a view:

JagFORUM Logon

I don't have time to go look at mine to confirm if I have the plastic or cast, just thought I would throw a (hopefully) helpful caution your way.

The author of the thread has a few pics in his album of the tubes and what happened to him.

 

Hi Red,

Photo number 3 in the album at the link below shows how I use a 1/4 inch drive ratchet with a short extension (about 6 inches long), a universal joint, and a 10mm socket to get at those hard-to-reach throttle body screws. Some guys have removed the air intake elbows on either side of the TB but I never have.

Welcome to Jag-lovers - Members Photo Viewing Page

If you don't have a 1/4 inch ratchet and socket set, with several extensions and a universal joint, I would recommend that now is a great time to invest in them because they come in handy for LOTS of work on the XJ40. My longest 1/4 inch extension is 24 inches long, but the one I seem to use most often is 14 inches long. It's great for undoing hose clamps in the engine compartment, the idle air control valve, the heater blower motor housings, and lots of other fasteners up to about 12 mm. The length of the extension allows you to reach into obstructed areas and get your hands well out of the way so you can turn the ratchet freely. (THIS ADVERTISEMENT HAS BEEN BROUGHT TO YOU BY YOUR FAVORITE BRAND OF MECHANIC'S TOOLS)

I'm glad Rob remembered that thread about those intake manifold elbows being plastic on some cars - good memory Rob!

Oh, and yes, it's the back side of the throttle butterfly plate where all the gunk collects, which is why we have to remove the TB to really clean it.

Cheers,

Don