My ECU has only limited communication with the ScanGauge: displays volts, RPM, horsepower and throttle position sensor. Does not show water or air temp, closed or open loop, nor oxygen sensors. This happened the previous winter, but everything came back when it dried out in spring. So far this year, no such luck.

I also cannot read or clear trouble codes. I have inspected and cleaned all the connections to the ECU, to no avail. I've also disassembled and cleaned all the ground headers, with the exception of the one in left front footwell (that one was unbolted from body and lug cleaned, but did not remove connector.)

Anyone else ever had this symptom? Any resolution ideas?

Oh-- And it's not the gauge. Works fine in the wife's' jeep.

 

I've had the same problems with regular scanners and it always goes away when I push the wires in to the back of the truck side connector. As thought the wires come loose from the connector...

 

I was hoping "Charlie for the win!" But sadly, no that is not it. Ran out and checked.

 

Oh. Me too. Dang!

Happens often with mine, because I have a scanner plugged in all of the time (its a rover).

I suppose it is possible that there is oxidation or some other stuff on the connectors but oh what a pain to spray electronics cleaner on them in the cabin. I'd exhaust all other possibilities first. But I can't think of any other possibilities at the moment. I've never found where the obdii port ends at the ECU, but if you can spot the wire colors that connector that might be the next one to check.

NOT doubting that the UG is good, but have you tried another scanner on the obdii port? If it is oxidation you could just plug and unplug again and again to knock of anything on the connectors.

 

What we have learned today so far is that Charlie is on his way to pull your motor and he is bringing brownies.

 

Pull my ECU, maybe. Charlie's suggestion did cause me to pull apart the on-board OBD II connector. Which helped me see the (4) wires connected to it: one purple, one mauve, two black. (The Rave electrical diagram is at home; I'm at work.) Seeing what part of the harness the wires are in, I was convinced the two black (ground?) wires terminated at the header in the right footwell. So I pulled that out and lo and behold there was a small amount of corrosion in the connector. Clean and shiny now, but no change in scan performance.

I hadn't thought of hooking up a different scan tool, but like I said, this scangauge 2 works fine in her jeep.

 

Haha hahah! Better yet! Found the problem. When I put the front cover on the inner gear of the oil pump pushed out, which is supposed to be impossible, and the main pulley crunched it. Sweet! Ordered a new oil pump. Now to take it apart all over again.

Sorry for the hijack!

 

Ha Ha indeed! No problem here about the hijack. Glad you solved your oil issue.

 

We may now have a clue as to why manual suggests using tool LRT-12-090 when installing cover.
......

 

Hahaha number9 you're the best! But I bet a new oil pump costs less than the tool.

Any suggestions for NickAdams? Mine was wrong.