high idle on p38 (pls help)
#1
high idle on p38 (pls help)
so i got a 1998 range rover 4.6 HSE and its driving me nuts... so it takes about 6 attempts to crank it and it still wont start until i go open the gas cap and then it starts immediatley... also when it does start it idles at 2000 rpm and doesnt wanna drop so its killing me in gas.
i had a mechanic look at it and he told me i had a leak and he changed my intake manifold gaskets and while everything was off he also changed my valve cover gaskets... he suggested i change the idle control valve, and i did and it ran worse the car didnt wanna crank.. while all of this was happening "no" check engine light came on till today.. and i got a code of p1177 and p1179 and idea what these are...
ppl have started suggesting that i change the
MAF
crankshaft sensor
tps
coolant temperature sensor
idle control valve
and camshaft sensor
has anybody gone through this to help me out so i dont go through all my money playing the guessing game:?
i had a mechanic look at it and he told me i had a leak and he changed my intake manifold gaskets and while everything was off he also changed my valve cover gaskets... he suggested i change the idle control valve, and i did and it ran worse the car didnt wanna crank.. while all of this was happening "no" check engine light came on till today.. and i got a code of p1177 and p1179 and idea what these are...
ppl have started suggesting that i change the
MAF
crankshaft sensor
tps
coolant temperature sensor
idle control valve
and camshaft sensor
has anybody gone through this to help me out so i dont go through all my money playing the guessing game:?
#2
P1179 Maximum Negative AMFR Correction Fault
P1177 Maximum Negative FMFR Correction Fault
This is probably your MAF acting up. Idk why uncapping your gas cap would have anything to do with it, but you might want to go ahead and replace it... since its cheap and it may not be venting properly. After that I would clean the MAF since it is also easy and cheap. If that still does not do anything. I would get a reading on the MAF sensor through an OBD scanner to see if the values are to low or high. You can disconnect your MAF sensor and see if it runs any better. Often times if its the MAF they will run a tad better when it is disconnected...
ppl have started suggesting that i change the
MAF= Probably the cause
crankshaft sensor= Doubtful
tps= Potentially (usually accompanied by fluctuating idles though)
coolant temperature sensor= highly doubtful (can be confirmed with an OBD scanner)
idle control valve= Potentially
and camshaft sensor= Doubtful
P1177 Maximum Negative FMFR Correction Fault
This is probably your MAF acting up. Idk why uncapping your gas cap would have anything to do with it, but you might want to go ahead and replace it... since its cheap and it may not be venting properly. After that I would clean the MAF since it is also easy and cheap. If that still does not do anything. I would get a reading on the MAF sensor through an OBD scanner to see if the values are to low or high. You can disconnect your MAF sensor and see if it runs any better. Often times if its the MAF they will run a tad better when it is disconnected...
ppl have started suggesting that i change the
MAF= Probably the cause
crankshaft sensor= Doubtful
tps= Potentially (usually accompanied by fluctuating idles though)
coolant temperature sensor= highly doubtful (can be confirmed with an OBD scanner)
idle control valve= Potentially
and camshaft sensor= Doubtful
#4
Same idle problem here ...
Mine is a '99 RR 4.0 GEMS with 195,000 miles.
On starting, idles at almost 2000, then once warmed up fully, if I turn off motor a and restart, it idles fine. Weird. Replaced Idle Air Control, no improvement. Will try disconnecting MAF and see if that does anything. Any other DIY suggestions? Thanks, Kevin in Minneapolis.
On starting, idles at almost 2000, then once warmed up fully, if I turn off motor a and restart, it idles fine. Weird. Replaced Idle Air Control, no improvement. Will try disconnecting MAF and see if that does anything. Any other DIY suggestions? Thanks, Kevin in Minneapolis.
#5
The following users liked this post:
wesleyfelixpsi (10-04-2022)
#7
#9
THrottle Pos. Sensor - oblong slots - more info?
RoverMasterTech;508982]It is your throttle position sensor. you need to oblong the mounting points and turn it back some.
Interesting idea, willing to try it out today.
Can you tell me WHY it might work - the theory? Is it to loosen up the tolerance in there? Is it jamming? And turn it back some - which way - either?
Thanks, Kevin in Minnepolis.
Interesting idea, willing to try it out today.
Can you tell me WHY it might work - the theory? Is it to loosen up the tolerance in there? Is it jamming? And turn it back some - which way - either?
Thanks, Kevin in Minnepolis.
#10
If your mechanic took it apart check your throttle cables first and make sure they're adjusted properly and in the bracket the way they're supposed to be. Mine did that and it was just that, nothing more. Putting the cable in properly into the seat and adjusting it was all that was needed.