Hi all,

Another notch to add to our Xj40's coming up - hope we all enjoy another maintenance-free year just like 2013

Did an intake service over the last couple of days as the car was running a bit rough and gas mileage was getting silly around town, 19L/100k (US12mpg) - plus - she's thrown a fuel fail 23 (O2 sensor out of range; rich) a few times over the last couple of months.

I took out the plumbing, throttle body, egr/evap port, MAF and cleaned out all the muck - and there was plenty! On a test run around town today, I averaged 14.1L/100k (US16.7mpg), so I must have done something right!

I had a problem with the 4 egr/evap port bolts especially the right side long bolts - I was expecting to have to fight with the large egr inlet pipe fitting, but that released pretty easily - maybe because on the '94 the pipe and fitting are stainless, I've seen other years egr pipes rusted up tight.

There wasn't enough clearance to remove or insert that rt front bolt - when I undid the port from under the manifold, the head of the bolt touched the top of the oil filter and wouldn't come out. However, there's a trick to it as I found out later


Anyway, my solution was to back off the oil filter until I could make room for the bolt to drop - luckily I didn't have to unscrew it off all the way as the car was full.

When I put it back together I had a hell of time trying to bolt it up but eventually figured out that the two right side (long) bolts had to be in the slots of egr port before putting it into position, that's the only way to get clear of the oil filter.

The bellows and hoses were full of sludge, same as last April when I cleaned out the bellows the first time. In September, I had the bellows off and it was completely clean so I'm thinking the Northwest damp winters are causing lots of condensation if the car only does short runs on cold wet mornings. Other than taking it out for a fast long run I think I might be stuck with a semi-annual cleanout.

The egr and evap ports weren't too bad, I'd cleaned them out from the top back in May by removing the IACV assembly, but wasn't convinced I'd got all the carbon (port was completely plugged) and suspected some carbon buildup remaining in the elbow or intake but surprise, those areas were clear.

The throttle body was fairly clean on the intake side but the back of the butterfly and venturi had a good buildup of carbon.

I doubt there was any 2 thou clearance left so the base idle was off and probably why I had a hard time setting the IACV accurately. Seems stable now, will set up the stepper motor tomorrow.

MAF sensor was varnish coated so I disassembled it and cleaned it out, and gave the wires a few squirts if MAF cleaner too.

(nice to see where the hot wires are located)

Fitted a new air filter but forgot to order it before I ripped the car apart - took a chance and called the local parts place downtown. They had one in stock and even though I'm not a garage and they don't know me from Adam, they delivered it in 20 mins for an extra $1.00, total cost $13.00.

When the guy handed it to me he said "thanks for thinking of us". I was stunned - they'll be my #1 aftermarket parts choice from now on, for sure. Real service!! Doesn't get better than that!

Have a good 2014

cheers

 

Great work Larry!! Thanks.

Now you can get back to helping the members fix their heat

 

Sounds like a good project for today! I've been meaning to give everything a good going-through after I saw all that condensation sludge.

Great write up!

Nick

 

Went for a drive today, everything seemed fine until I stopped to pick up a few groceries - when I re-started the car, boy was it running rough!

I couldn't get it out of "P" without stalling and it sounded like it was running on 3 cylinders

Anyway, popped the hood and started checking electric connections, starting with the MAF connector and then I saw what the trouble was - the vacuum hose from the IACV to the elbow was completely off at the elbow - I'd forgotten to tighten up the hose clamp I guess ...DUH

Popped it back on and tightened the clamp and all was well again! Phew!

 

Love those types of repairs any day, anytime.

 

Lawrence,

Thanks for this write up and pics. It looks like a good job to undertake on a rainy day and since I need to change my oil and filters, might contemplate doing this at the same time.

Quick question, were there any gaskets that needed to be replaced in the process? Or did you just reuse any that were there?

Also, you mentioned that your base idle was off and you had to set the IACV. Is this something routine when doing this or can a lay person get away with just stripping, cleaning, reassembly without any adjustments?

Thanks Again

 

Hi, the only gaskets you might need are the two that are used on the EGR housing under the manifold - but - if you're careful removing the housing you might be able to re-use them. I was able to re-use mine but I added a bit of sensor-safe silicone on re-assembly. The throttle body to manifold is metal-to-metal, no gasket used. You're going to need a socket with a u-joint and short extension to get the lower throttle body bolts off, there ain't much room in there!

You may not need to readjust the IACV if the settings haven't been messed with - (mine was off because the PO had tried to compensate for the dirty throttle by changing the air bleeder setting)

Clean the throttle body, EGR/Evap ports and plumbing out and fit a new air filter and see how she runs. Wouldn't hurt to run a bottle of fuel system cleaner in a tank of gas either, a good one with high concentration of P.E.A. is just the ticket to get rid of the rest of the carbon in the intake ports and valve stems/injectors. (Techron, Gumout Regane hi-mileage, etc)

Changing the oil filter is easy with the throttle body off, so good time to do it. Small tip: two hoses attached to either side of the throttle body will drip coolant when removed from the throttle body so have a couple of plugs on hand to plug them up while you're in the shop cleaning the throttle.

I get way better mileage and smoother running since I did the intake service, hope you do too!

Cheers

 

Well It'd been a couple of years since I did that big intake cleanout so after having those stumbling/stalling issues last month I thought I might as well pull off all the intake plumbing and do it all again...

This time things weren't anything like as plugged up - there was SOME milky muck in the big rubber accordion, but nothing like last time.

The throttle plate had some carbon buildup, but again, nothing like it was a couple of years ago. A few squirts of carb cleaner and the throttle plate and body were all clean.

I also checked the tps voltages while I was in there and happy to report all is within spec.

The weird shape T hose EAC7487 (I believe but I may have that wrong!) that runs from the cam cover to the heater element on the way to the elbow always was a bit suspect and it's really looking sad at the cam cover end now!

Its got a good split happening and although I've sort of got it sealed I'd really like to replace it.

You can see the hose I'm talking about in the photo of my engine intake above.

I thought about making up a hose to match from short pieces and copper pipe fittings maybe - anyone else tried this?

Larry

 

Larry,

I don't know why that wouldn't work, especially if you could find a reducing T-fitting with the correct diameters in copper or high-temp plastic. A guy on the X350 forum replaced some of his breather hoses with a combination of copper and PVC, but the PVC he used was clearly marked with a maximum temp of 140F, which is probably too low a limit on top of an engine.

I'm guessing you'd probably want something good to at least 250F to survive underhood temps on hot days. I know they make T-fittings for heater hoses, but those only get as hot as the coolant. I assume the crankcase gasses can get hotter than the coolant, given that they contain combustion chamber blow-by, but maybe I'm wrong.

Seems like you ought to be able to do it!

Cheers,

Don

 

Yes I''ll probably make up a fitting to replace it - ordinarily I'd just go ahead and order one but can't really determine the part number!

The illustration on both JHP site and JEPC only refers to earlier models with the oil filler outboard of the cam cover, (the 94 hose is quite different) so it's all a bit unclear. Very similar to the cam cover "number of fasteners" issue where JHP insisted that my cam cover couldn't possibly have 13 fasteners as it is well documented that the XJ40 only has 7!!

Larry