First, let me say hi to everyone. Super long time lurker and thourougly enjoyed
and appreciated all the posts I've read. In the past, should I be experiencing a problem, I could do a quick search and find answers. However now I have a problem and can't figure it out.
93 YJ 2.5 5Spd. Driving down the road at any given time, everything runs fine, no problems, come to a stop and my idle wants to sit at about 500 RPM, a little too low, kinda shaky. Now here's the riddle/problem, lets say I'm driving at any speed, lets say 40 mph like I did today, drop the clutch and slip it out of gear, release the clutch and coast. While coasting down from 40 mph I'm watching the tack, it's sitting at or a little above 1k RPM and stays there until about I'm nearly stopped, then drops back around 500 rpm. I can't figure it out, I have no load on the engine at all during coasting, not applying brake, nothing but it's own momentum. Why is my idle staying where I would like it, but then dropping low, just a few rolling feet from being stopped?
Thanks again everyone. Hopefully I can be more of a contributor than a lurker from now on since the ice is broken.
Have not checked codes, don't have a scanner. If it matters, just went through
emissions a week ago. But then again, this is an older OBD system and they didn't check, at least I didn't see them plug into the connector on the driver side firewall.
Don't need a scanner. Turn the ignition on, off, on, off, on, off then on. The check engine light will flash. Codes are two digit numbers code 12 would look like flash ...... Flash, flash. 33 would look like flash, flash, flash .........flash, flash, flash. At the end of the codes you'll get a 55. That means end of code sequence.
Once you write down all the codes and double check them post up and we'll tell you what they mean!
No A/C, so that makes sense. I had already planned to clean the T/B and IAC, I was just dumbfounded why those two items would have anything to do with just coasting, except for maybe airflow through the T/B. Thank you for the help.
A little more information for my problem. Today coming home from work I intentionally and patiently messed around to see if I could get any more thought as to why this is happening.
I found a piece of road that would allow me to coast for quite a distance without any help from me, via gas pedal. What I found out was, I could literally coast along around 3 mph, (I had my GPS on to verify speed), and the idle would stay around 1000 RPM. 3 MPH is about what the average person walks, pretty slow in comparing to vehicle speed. But as soon as I get just about to a staop, RPM needle drops to around 500 RPM, rougher than I would like idle.
I'm wondering if the VSS-Vehicle Speed Sensor is the culprit. Anyone care to comment please?
My 95 2.5L did the same thing last week but would idle too high for way too long, got some carb and linkage cleaner and scrubbed the TB intake and just cleaned er up nice and now it settles around 750 rpm,
95 2.5L, 5sp, 4" RC Lift, Lock Right front diff. 8.8 LS 4.10 gears, M/T 31" Baha Claw