some obdII to obdI questions

[jakeb]

Took the intake manifold off my s52 today and I have a couple questions about the obdII swap. Currently I have a m50 in the e30 and will be going over to a s52.

First in my head where the 2nd coolant temp sensor would be on a obdI engine there is a plug in it. There is a 96 year code stamped on the back of the head so could it be a left over casting and they just plugged the coolant hole? So I can just remove and use my OBDI sensor? Has anyone seen that before?

Second is there a reason to not use the metal coolant pipe rather than the rubber spider hose? I had planned on getting the glue in fitting to use the spider hose but if the metal line working fine I will use that.

TIA

[hugh jass]

if you can unplug the plug in the second sensor port, go for it. on most obd2 engines you have to drill and tap the second port
no reason you can't use the metal coolant pipe. that's what i did. i had to cut a coolant hose to fit between the pipe and the pipe on the firewall but it works fine. one less rubber hose to worry about under there!

[atldohc]

i am currently in the process of prepping my s52 obd1 conversion for installation as well. in the first pic you can see where i marked the spot to get ready to drill and tap for the gauge sensor. in the second pic you can see where i decided to just remove the coolant nipple on the right and use that hole instead, since im deleting the tb coolant hoses. in the hole on the left, where the obd2 dme temp sensor was, i just took it out and installed the obd 1 temp sensor. on the right hole i had to enlarge the hole and tap it, because the threads on my e30 gauge sensor were larger. for me the threads were 14mmx1.5mm. if you have that plug just take it out and see what size the threads are. then you can decide how you want to do it from there. hope that is of some help to you