accord_raffi

Second thread of the day. I apologize. Anyways, I noticed this happen twice now. I'll be driving and as I'm coming to a stop, if I press the clutch in while my speed is a little high (roughly 25mph), I'll notice the revs drop to sub 500 rpms. Yesterday and the day before, the car actually stalled from the revs dropping so much. So my first assumption was check the master cylinder and slave. I don't think it's the slave because i'm 90% sure that was swapped out by the previous owner before I bought the car. If I wait and press the clutch at a lower speed, then the car is fine and the revs stay normal. Any ideas?

aasaa666

the MAP sensor will do that. Its one of those sensors that doesnt have to be dead in order for you to tell that its bad, kinda like the HOS.

98civicboy69

my motor is doing the same thing!! i have no clue either....any help

98civicboy69

i was told it was my injectors needed cleaned or my fuel filter needed changed so i bought a new fuel filter and replaced it and got injector cleaner and ran it through and it still is stalling not as much but still is

accord_raffi

Idk but I don't think this is fuel related otherwise I would be bogging in other rpm's. I don't think it's the MAP either because I have an air/fuel gauge and I'm reading the right ratio throughout the power band so the MAP is doing its job fine. Anyone else have any input? I'm still banking on master cylinder...

accord_raffi

Now that I'm thinking about it I feel kind of dumb. This might be more related to something electrical. I'm pretty sure it's dropping revs AFTER the car is out of gear, but i'm going to double check that. If it is dropping after I pull out of gear, I feel like it has to electrical.

aasaa666

whatever the case, I've just given you a possible solution to your problem. I had the same problem, I drove around with that same problem as yours until my MAP finally went dead and then it ran like dung.

AFAccord

It can't be related to the clutch release system. Likely electrical like you stated.

I would ponder whether your IACV is gunked up, and unable to open fully and quick enough to 'catch' the falling revs.

aasaa666

im not gonna talk about the MAP Sensor anymore. anyway, it is irrelevant. just because you set the base idle doesnt mean it wont dip below. you can sit still in your car and turn the steering wheel and cause the rpm to dip, you can quickly turn on all electrical load and watch your needle dance. My IACV being gunked will only cause it to not idle smoothly when it needs to compensate.

accord_raffi

I know it can dip below where my base idle is. I'm just saying it's not my MAP b/c if the voltages were off at the MAP, fueling along the entire RPM range would be off, too.
I appreciate the response!
As for the IACV, I'll take another look at it. When you clean it, do you clean the hole on the right as well without the screen? I cleaned the screen only last time and that was about a week ago. On a dsm forum, apparently someone had the same symptoms and rebuilt his MC and it was gone...I didn't have problems with it yet today.

accord_raffi

Well it started doing it again. Even if the car is out of gear so it must be electrical related. Maybe TPS? bump for support.

accord_raffi

bump

Rust_is_euro

just throwing it out there... maybe a vacuum leak?

accord_raffi

no because i would noticed my vacuum gauge having off measurements. thanks for the reply though.

accord_raffi

well just cleaned the iacv and tightened the fitv. hopefully that will do the trick. the fitv was had to be turned more than 2.5 turns! the guy in the write up did 1 and a quarter or 1.5 i think

accord_raffi

well it stalled the first drive after i did it. anyone have input? cam/crank sensor?

billyrusa

I had the similar problem and had been working on this issue for over a month. The RPM occassionally dropped or sometimes engine stalled when at stops, especially when a/c was on. I cleaned IACV and changed FATV because it is bad anyway. The problem was not resolved even after changing the fuel filter. when I was going to buy a fuel pressure tester to check if the fuel pump or fuel pressure regulator is bad, the car went to its worst -- idle very roughly and there was not enough power to drive. Because of this, I finally figured out one cylinder did not work. After changing spark plugs and wires, the car starts running without any problem. I believe the original occasional RPM drop was just misfire and it is electrical related. This is my case, hope can give you some help.

accord_raffi

my plugs have about 3k miles on them and the wires have even less than that...that helps though. then next time i notice my rpms dropping, i'm going to watch my air/fuel meter to see if it's rich or lean. If it's rich, i'm going to assume it's ignition related (good thing you brought that up billy). If it's lean, i'm going to assume it's poor fuel delivery which could be caused by a bad cam or crankshaft position sensor. i'll keep this updated.

billyrusa

It also happened to car -- If the car runs worse when it is raining or high humidity, it is probably an ignition related problem.

accord_raffi

well it was raining and humid last night when this happened. drove it like 5 hours after i cleaned the iacv and adjusted the fitv.

accord_raffi

Does a 1996 accord lx only have a crankshaft position sensor? rockauto.com only shows options for the crank position sensor, but nothing for the cam.