Does a cylinder tend to run hot/lean on the 2.0 engine? Options

[pisces914]

hey guys - is there a cylinder that tends to run hot/lean on the 2.0 engine? -

i'm not exactly sure which cylinder is which, but i believe the #3 cylinder (pass side, rear) has the head temp sensor on it - that leads me to conclude this is possibly a cylinder that runs hot/lean -

any info (or corrections to my thoughts) would be great -

this regards my placement of an O2 sensor -

thanks, brad in seattle

[914itis]

I am not sure about lean, but yes #3 runs hotter.
And you are right about the reason the temp sensor is there.

[pilothyer]

As for cylinder # 3, it does tend to run hotter due to the air being directed to the oil cooler and cylinder #4. VW distributors used to have built in retard for cylinder # 3 to compensate because it runs slightly hotter. Not sure if that is still in use with type 4 now but if it is it would be very important not to rearrange the spark plug wires on the distributor.

[r_towle]

Yes, number 3 is the hottest.

For an O2 sensor you really should try to get it near the mixed merged end, yet still hot.

I use a tailpipe version for tuning, I figure after its tuned, it's TMI for me to watch.

Others have installed them in merged collectors from Busch, or triad..
Foley also has a few locations he suggests.

[pisces914]

Yes, number 3 is the hottest.

For an O2 sensor you really should try to get it near the mixed merged end, yet still hot.

I use a tailpipe version for tuning, I figure after its tuned, it's TMI for me to watch.

Others have installed them in merged collectors from Busch, or triad..
Foley also has a few locations he suggests.

thanks, i will speak with chris foley - i have used a buddy's innovate LM-1 air fuel gauge with great success to dial in my MPS settings on a 2056 build with more displacement, compression, cam, but with stock EFI

i decided to purchase an innovate O2 sensor/gauge set up to permanently install in my 914 - i called innovate tech after i read their instructions NOT to install the O2 sensor in a muffler - tech told me that their recommended practice is to find the hot/lean cylinder and to install the O2 sensor down tube from there - that way your tuning doesn't get a lean cylinder too lean, which is my goal

at first, i preferred the idea for the muffler install (i have a triad) but when i ran this by several of my more sophisticated than myself mechanic/engineer porsche pals, they agreed with innovate

from what i understand here, cylinder #3 runs hot because of cooling issues - does the cylinder temp have any causation for lean/rich running?

thanks, brad

[jeffdon]

Yes, number 3 is the hottest.

For an O2 sensor you really should try to get it near the mixed merged end, yet still hot.

I use a tailpipe version for tuning, I figure after its tuned, it's TMI for me to watch.

Others have installed them in merged collectors from Busch, or triad..
Foley also has a few locations he suggests.

Anyone make an inexpensive tailpipe sniffer that is good for tuning? I do not want a permanently installed A/F meter for the above reason.

[michael7810]

I have to agree a permanent AF meter is TMI most of the time. Only time it came in handy is when I spent a few days driving in the mountains and had to change the jets.

[pisces914]

I have to agree a permanent AF meter is TMI most of the time. Only time it came in handy is when I spent a few days driving in the mountains and had to change the jets.

i agree to a point - i am going to have the gauge and O2 sensor removable for regular driving - i am going to have this installed for any changes to EFI, track days, altitude adjustments, and very long trips