So im getting an intermittent P0193 and more recently a P0087 codes showing up.

This is pointing me to a bad fuel sensor (even though I just replaced it with an OEM one). Good thing it has a warranty.

Going to replace it and see if the codes show up again. If not, I'll have to do pin point tests ... ughhh.

Any suggestions beyond that?

With the original one leaking and this one failing, I sure hope there is nothing seriously wrong with the fuel system.

 

Ended up unplugging the connector, cleaning it out, and plugging it back in nice and firm. Haven't seen the fuel sensor codes show up in a few days so I think all is well.

Got the catch can installed too and it's running pretty well.

Changed the o-rings on the full load breather and oil dipstick just to be safe, but I am still getting P0101 on the highway. .. unbelievable.

Only possible sources left for the vacuum leak/P0101:
- bypass actuator to throttle elbow hose (unlikely, since I clamped both ends and visually inspected it for damage, nil findings)
- purge valve to throttle elbow hose (also unlikely since it's sealed by 2 o-rings and they both looked good and tight after cleaning)
- PCV valve to valve cover - hissing noise is still coming from here, and since I secured a new hose setup it must be coming from the bottom of the PCV valve
Still not sure how to seal it into the valve cover effectively, but I have a spare PCV so I will play around with that

 

Oil dipstick on a X150? Where?

 

4.2L has a dipstick

 

Your pcv valve the round unit is suppose to hiss , I thought something was wrong with mine when I got the car so changed to new one and it hisses.
P0101 is maf code and does not indicate a vacuum leak, but mostly likely a bad maf unit, had to change mine around 70k miles due to the cel light
Easy way to check vacuum leaks Check your long term fuel trims if they are + high , than you probably have a leak if they are normal you don't .either way most likey need new maf sensors

 

Not sure how that's normal ... I never heard it before then all of a sudden it starts doing that a few months ago.

Both banks combined fuel trims are over 10 (EDIT: both combined are around 15-20), and I already changed the MAF sensors a few months back.

I brought the car to the dealer Monday and even they agreed there is a vacuum leak (they got readings directly from the MAFs and said they were good).

Would the SDD guide them on MAF pinpoint tests?

They say they can't diagnose any further until I put the stock PCV hose back on without the catch can - but I already got all the info i needed from them.

 

Last thing first... Pull it back apart and you'll find your cuplret...

 

Fuel trims combined, you reffering to long trims not short yes? 15-20 is higher then it should be so there is a leak. You changed both Maf units with Denso oem brand yes? Anything else will not cut it in our cars . Do a smoke test , easy to find leaks that way
And yes under normal idling conditions the round pcv valve will emit a hissing sound, now you can still have a defective one and maybe that's where your issue is

 

Smoke test is a good idea, but i think you will be fine going back to original breather setup....the ufo valve is not a pcv valve because it can flow both ways...i think your new breather hose was sucking more unmetered air than the pcm will allow without setting a code...mafs codes are a reaction to the higher trims....higher trims are a reaction to the increased breather capacity....pcm thinks the maf is faulty....you could retune the pcm to your new setup like has to be done with supercharger boost increases that go outside the pcm ability to compensate at factory settings....this assumes of course you pass a smoke test....either way, excellent work on your redo under the hood....i am sure it will be something simple....you should car show your work

 

Fuel trims in my experience on these cars will not ever set a MAF code , but will set a lean code for both banks if too much correction is applied. I do not believe in your case maf code has anything to do with the leak

 

You are right, i was thinking lean but related it to maf and not trim values as being able to set a lean code.maf is generally by itself another issue

 

Theres no going back to the original breather. The pipe was cut and they don't make the part anymore. Wouldn't matter anyway because I had the problem before and after. I doubt the new hose has any leaks, I put it on there nice and tight.

I've seen some videos on people making their own smoke machines, so i'll look into that for testing.

I'm convinced it's a leak, and I also realize it doesn't have to be a vacuum leak, it could be anywhere between the MAF and throttle.

Also read up on brake boosters, those can be a source for vacuum leak also, so I'll see if I can test out the booster to make sure it is good (not the pipe or check valve, those were replaced, but the booster itself).

If all else fails, I'll do what I should have done in the first place, pin point test on both MAF harnesses. Does anyone have a procedure for that? How do I know what the voltages and resistances are supposed to be? Not sure it they are listed in the electrical layout.

 

For anyone interested, here is a part list and some guiding steps for the job.
O-rings for vacuum and breather lines are not on there. As well as cleaning cans, masking, paint, misc tools, etc...

 

Just to follow up on the issues ...

P0193: after doing pinpoint checks everything looked good. Seems the harness was getting pinched between coolant lines, causing an intermittent short. Re-positioned the harness, taped one of the wires, and haven't seen the code return all week.


P0101: Made a smoke machine and tested the vacuum system. Found a leak at the oil filler tube (bad o-ring) and replaced it. Haven't seen that code pop up in a while either.


On to trouble free summer driving....

 

These are all the same things I am going through- P0430 followed by - P0302.p0304,p0306, p0308 car will drive great for 100 miles then falls over with these codes

They started after letting car sit a long time without starting it or running engine.
Basically - traced to from bad O2 Sensors (Burned up) due to engine issues
random misfires - changed all plugs, and moved Ignition coils around to find the issue stayed with the cylinder.
Went from Random misfires after new plugs and ignition coils checked to just misfires are 2,4,6,8 which is left side seemingly at random.
Due to the gas siting in car for 6-9 months I suspect the varnish and junk settled in injectors so preparing to pull injectors and clean out the fuel rails too.
Car has 47000 miles so hoses are still pliable and wiring has not hardened yet. I just started the top end tear down.
I have a serious buyer lined up, so need to get it done right the first time LOL no pressure.
Thanks to this post my intuition is correct - remove blower, and plenums to get to fuel rail and injectors - lovely... I have new intake gaskets, getting new injector o-rings and injector puller.
still easier than a Lexus SC400 timing belt replacement.

 

Truly appreciate the post here and all the good work and documentation.
I have taken everything out and there is oil in the intake runners - not much but some not sure what is normal I am used to not having oil blow by unless there is bad valve guides or something.
Reason I am doing this is the getting misfires on the left side 2,4,6,8 and p0430 code - I moved the ignition modules and replaced one and issue stayed with cylinders - moved one ignition coil to the right side and codes still on the 2,4,6,8 - so I am pulling fuel rail and cleaning injectors hoping that solves it.
As a side note there is a Tahoe PCV vacuum hose that is nearly identical to the JAG - I can check if it fits...
Also I found the 2005 to 2007 Chevy Tahoe injectors and o-rings are nearly identical in diameter and thickens so using the o-rings at least when putting injectors back. considering testing the tahoe injector in comparison tot he JAG injectors would be interesting if they perform the same.
I am video taping everything... not painting anything red as that is plagiarism LOL instead just going to clear coat all the parts so they stay shiny.
Let me know if this should move to another thread - otherwise will keep it here since it relates to this original post.

let me know...

 

just because they are same size does not mean they flow the same. I would not risk it without first figuring out the flow rating of the Chevy Tahoe injectors to make sure they flow enough. Last thing you want is lean condition and blowing up your engine. If they do flow the same or more we can tweak the ECU tune to accommodate for larger injectors so you're able to receive correct air fuel ratio otherwise you will be too rich..

 

agree on the flow characteristics just thought it would be neat if they are similar.
After taking the intak plenums off there is alot of oil - I think combination of bad gas fouling injectors the PCV may have been stuck allowing a lot of oil to get sucked in.
right now its clean valve stemdelicately and ultrasonic washing of the injectors and bench test tomorrow.





these are pics before and during cleaning

 

so an aftermarket pcv valve can cause heavy oil injection. Only use OEM jaguar PCV valve, had several customers put on aftermarket units and had issues with smoke. Put an oem one and issue is gone

 

Hi Folks -
Ordered a new PCV from JAG and the one on the car had FOMOCO JAG on it so it was the original - car only has 47k miles on it.
The PCV was stuck so tack on, car sat in a garage for 10 months, bad fuel, contaminated fuel rail, loose ignition coils, bad plugs (fouled) and finally no oil Change as the oil filter was a JAG oil filter from what I guess is a year ago.
4 engine flushes, 2 VVT solenoids, Injectors cleaned, New Spark Plugs, 2 ignition coils replaced, New valve cover gaskets to include the spark tubes as they were beginning to seep oil, this car better drive like new.
I have to replace the fuel filter and I am rigging up a vacuum jug (3 gallon Car Boy and a siphon hose into my coolant jug) to pull coolant through system so no air bubbles, then test drive hopefully Saturday.
wish me luck - oh and fastening the throttle body to the elbow to the super charger and the upper intake plenum or whatever those are called I used a 4 foot piece of 3/8 fuel hose under it as a sling and pulled it up into place to get all the bolts started by hand then tightened in a cross pattern worked great until I realized I was using one size too small torx bit... have to get a new sealing bolt as I damaged the head of the bolt tightening it. $9.00 a piece from JAG ouch...
any who its back together everything looks tight the injector flush was definitely needed - had to sonic was the left side 4 injectors 4 times then reverse flush a couple times sonic wash again reverses flush, then cycle through tests 3 times before they were flowing evenly. that oil and bad gas really messed things up... the right side was not reporting any misfire codes and those were just sonic wash and test and worked great. I put them ALL back in the same spot except for cylinder 2 and 8 injectors just to see what happens there. I thought about swapping like 2 and 3 cylinder injectors for grins and giggles, but figured better to put it back mostly as it came out.

I will post pics and updates once complete.