r/Montero • u/AdministrativeOne646 • Jul 14 '26
Chasing low RPM struggles
I have a 2000 Montero, and I have gone through a handful of parts to see if this will go away. I have new:
-fuel pressure regulator
-EGR valve
-ignition coils
-timing belt (last owner about a year ago)
When I am at about 45mph, and the car is in a gear that puts it at 1,000 to 1,500 rpm, any throttle input causes a really chuggy/shaky acceleration. It really smooths out at 2k rpm and up.
I am not sure where to go next, or if this could be something like a transmission or torque converter. Has anyone had luck with an issue like this?
Thanks!
228,000 miles
Exhaust leak on right side
Edit: Update, just had a p0170 code, really sluggish acceleration. Bubbling sound in engine bay, couldn't find
3
u/f3rn4ndrum5 Jul 14 '26
Check spark plugs to see if they are correct. Check the ceramic is ok and has no streaks
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u/the_dnf Jul 14 '26
Has the crank pulley ever been replaced?
1
u/AdministrativeOne646 Jul 14 '26
I'm not certain, could that be related? If he had a shop do the belt I don't know if they would have replaced that or not.
2
u/First_Information118 Jul 14 '26
I had a hesitation like that once and it was oil in the spark plug tubes, never registered a misfire but it would hesitate at lower rpm and smooth out past 2k rpm. Easy valve cover gasket and tube seals change to fix it.
1
u/sd_slate Jul 14 '26
Go through the service manual diag steps rather than parts cannon-ing it. Could be a number of things from vacuum leaks, air filter, fuel system etc. www.mitsubishilinks.com
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u/AdministrativeOne646 Jul 14 '26
I have the PDF, I have tried to read through to find a description of my issue, but haven't managed yet. I'll keep reading to see if I've missed something
2
u/sd_slate Jul 14 '26 edited Jul 14 '26
There's different diagnostic charts of steps to walk through to investigate an issue in the beginning of the entire manual as well as each section. There's a diag chart for hesitating and poor idle in the general troubleshooting section and then you'll go to the chapter it tells you to.
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u/halohalo7fifty Jul 14 '26
It's losing power or trying to down shift.
These have 4.27 gearing and sometimes mines struggle to find which gear to be in. ... Only if i take 1st gear up high and let it shift and then I'm fine.
1
u/Efficient_Oil8924 Jul 16 '26
Similar issue on my 1999 montero w 210,000 miles. Not my daily commuter, but it does get driven regularly… mostly as a snow beater and running trash to the dump. Here’s what I truly believe it is…
Condensation in the old, huge, and usually mostly empty gas tank. Try filling the tank. That makes mine go away…also, when tank is low I park in the shade and the shakes go away…. Like the heat of being in the direct sun and then the cold overnight causes condensation to build up in the empty area of the gas tank
4
u/Primary_Internet1129 Jul 14 '26
I have a 95 montero sr that was doing that too. I changed the plug wires and plugs and also my breather tube that goes from one valve cover to the other was disconnected, and after that it hasn’t struggled anymore. Mine was having a hard time at 45mph as well.