Hi Everyone,
In my endless quest to solve the cold stalling under load problem, I removed the throttle body and cleaned it. This didn’t solve the problem. I noticed once the throttle body was off that there are two metal tubes in the engine just beyond the throttle body, one slightly larger than the other. They terminate with open ends and were full of solidified oil/carbon. I cleared them out with a flat tip screwdriver and vacuum cleaner. I might attempt to clean them better. What are they for? Is it part of the EGR or PCV system? They seem to be just above the oil pressure sensor. I did notice a metal pipe with some heat shielding material going into the engine block nearby to the oil pressure sensor. I didn’t know if that’s one of the pipes that I saw inside.
Darren -
I can only think of the EGR pipe in that location with a fibre heat shield and that pipe attaches to the RH side of the EGR port assembly bolted to the underside of the manifold. That assembly does have two metal “tubes” and the one on the right is the EGR port.
These ports are especially prone to carboning up and that WILL affect smooth running, so you’re on the right track.
You can remove the port assembly to do a complete clean-up, there are four bolts holding it to the intake manifold, along with the egr pipe large nut on the right the electrical connector and the hose on the left. When you get it off and cleaned up, it looks like this:
IIRC, after cleaning it up, you have to put all four bolts back in place before bolting it because the oil filter prevents a couple of the bolts being inserted if you bolt them up one at a time.
Here it is all shiny and back in the manifold:
Some folks clean the EGR port from above too, I did it this way at first (by removing the IACV; port is directly below) but for best results I’d advise removing it
all the best
Larry.
Hi Larry,
Thank you so much for the information. Your pictures are exactly what I was describing. Can I assume correctly that the electrical device is the EGR temperature sensor? I have operated the EGR valve manually with my fingers and in doing so, I can verify that the engine will stumble upon idle like it should. Does clogging of the smaller port cause idle problems? I see that the rubber hose appears to connect to the smaller port. Is this a vacuum port? Thanks again,
Darren.
Can’t remember exactly Darren but I THINK the left port is the connected to the purge valve down by the carbon canister … may as well clean them both up if you’re in the neighborhood anyway, right? 
Thanks again Larry!
I will go back in there when the snow is over. I must say I do love the snow, even if the cat must stay in the garage. This car has never, ever been in the snow!
Hi Larry,
What is the electrical connection for? Is that the EGR temperature sensor?
good question! - I’m not sure Darren but that does sound reasonable 
If I recall correctly if the EGR port clogs up the EGR temp sensor recognizes it is not working correctly and flags a check engine light and code.
I don’t think so John - (at least not on my car) …The EGR port was so clogged on my car when I got it that I actually refused to believe I had an EGR port fitted 
…completely buried under a mountain of carbon …however …nary a code displayed …rotten idle/stalling/hesitation and general crap running though 
Of course it was only one symptom of the problem, entire intake was choking from muck and general lack of maintanance.
Well you could be right, however, I recall some years ago with my 1990 XK40 a check engine light came on and it turned out to be the operating solenoid for the vacuum controls had failed but the light was set because there was never the proper temperature sensed at the EGR port since the EGR valve did not work. At least that is how I remember it but it must have been 15 years ago. My car only has 70,000 miles on it and I’'ve had it since new. I would think that if the port clogged up there would be a temperature issue as well.
John Quilter
Eugene Oregon USA
Sorry John, out of my depth here 
- I’m up on cleaning the port in the manifold and the role of EGR, but have not a clue to the inner workings of the EGR solenoids/temp sensors.
Touch wood but I haven’t had a problem in that dept (yet) @ 211,000kms 