I have a 98 disco with over 200000 miles. Engine was weak and had low oil pressure. Final straw was 3 rocker arm tips wore off causing knocking noise. Found another 98 disco wreck with 85000 motor sounded and ran good. swapped complete. used original exhaust manifolds and upper intake manifold. Enigine starts and runs great, no codes, but will not idle. average idle is 1800 rpm, put in gear it will drop to 1200 rpm. No vacum leaks, clean functional iac motor. Whats next?
98 disco with 2000 rpm idle since engine swap
- Thread starter chip2tx
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Disco Mike
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If the t/body is dirty, clean it, if that doesn't fix it then you have to have some some reset the IAC to your ECM which regulates the idle.
I tried removing batt positive cable for about 10 minutes. When reconnected idle was ok. Truck ran great for about a week. But we had a cold front blow thru yesturday and temps dropped to the 30-40 degree range. Now the fast idle has come back 2000 rpm in park 1200 in drive. The cable trick didn't help this time. As far as reseting the iac to ecm does this have to be done at the dealer?
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Yes this required either the dealer or someone with autologic computer for LR's.
wolf
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Same applies to the tps - even more so - i.e., if you replace your throttle position sensor - to prevent hi or searching idle - you must have a LR dealer set the voltage via Test Book.
Wolf
I had the same problem and I am too stuborn/independent to pay a dealer! My scan tool showed 16% load value (from throttle position sensor) with throttle fully closed....so I enlarged the TPS mounting holes (to effectively make them slotted) installed TPS, adjusted as little "on" as I could (10% according to scan tool) and it now idles perfectly!
I know, shouldn't work
(I've been an auto tech for years) but it did. Easy fix, let us know if it works for you.
I know, shouldn't work
(I've been an auto tech for years) but it did. Easy fix, let us know if it works for you.
wolf
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re: tps idle
Let me get this straight - you made the mounting holes in the tps itself slotted or oblong so that you had play for manual tps adjustment? That actually sounds like a good idea and it keeps you away from the dealer and their uber-pricey Test Book analysis!
Mucho kudos to you!
Wolf
I had the same problem and I am too stuborn/independent to pay a dealer! My scan tool showed 16% load value (from throttle position sensor) with throttle fully closed....so I enlarged the TPS mounting holes (to effectively make them slotted) installed TPS, adjusted as little "on" as I could (10% according to scan tool) and it now idles perfectly!
I know, shouldn't work
Let me get this straight - you made the mounting holes in the tps itself slotted or oblong so that you had play for manual tps adjustment? That actually sounds like a good idea and it keeps you away from the dealer and their uber-pricey Test Book analysis!
Mucho kudos to you!
Wolf
I have a cheap scan tool that I got from the snap-on tool truck for 89.00 it will read and clear codes and do real time data stream and snapshot data. And it comes with 1 year free updates but usb cable and the internet. It was built by Autel (new to US) It is a AL309 model that can be purchased from their web site www.Autel.us. Their web site shows a bigger one about to be released which is suposed to be a full function scan tool for all eropean engines, and specificly list Rovers and BMW. I am impressed with this base model for cost and function.
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