Hi all,

I've been having a problem with my FD where when the car comes to a stop from a roll, the idle drops massively and the car will die unless I heel-toe under braking.

It was pointed out that the dashpot could be the problem, so I took a look, and checked it out.

To me, it does look and feel kinda weak...when I looked straight at it, it wasn't even touching the lever, there was about a 1/4 inch gap between the lever and the white button. Even after loosening the locking nut, I could get it to touch, but it was really spongy and didn't offer much resistance at all. Is there supposed to be alot, I mean is it supposed to be firm, and hard to push?

Here's a pic of it's current state. Does anyone have a photo of a newer one to compare, or can anyone tell me if this thing needs to be replaced? Or is there some way to take it apart and clean it up a bit to get it to work?

Thanks!

 

does it slow the throttle down at all? The button should have some resistance, but not so much that the throttle will not close at all. its hard to know how easily it is for you to push it in. If it feels very loose and just pushes right in with very little effort then it probably needs replaced. If it does put up some resistance and doesnt just push right in when you touch it then its probably alright. without touching it for myself i can't really describe it any better..

 

It does have the capability to slow it down...I just checked out another dashpot from an engine a shop owner I know has, and that one felt weaker than mine.

I can't test it for sure because my car is taken apart trying to fix a fuel leak on my aftermarket FPR...but since I had the UIM off I figured I'd take a look at it.

Maybe it's just best to replace it anyways...it's 93, so it's about as old as an FD can get. I'd rather be safe than sorry, even if it costs a few bucks.

Is the best place to order from Malloy? I live in Hawaii, and the local dealerships rape us on parts.

 

That dashpot does appear to be a little weak. In the FSM the dashpot should extend out to the throttle linkage until 2800 RPM where it then breaks contact at higher RPM.

I actually had the same problem you do and replaced the dashpot. It ended up being the TPS that was off. New dashpots were around $90 last I checked. Here is the part # N3A1-20-190.

 

Thanks a bunch, Oblique...appreciate it. I'm just now getting around to getting this thing sorted. I've had it since 2001, and I've only put 5,000 miles on the thing.

 

i say try it out. since it wasnt even touching before, it did nothing. It's super easy to take out so you can always replace it later if the problem continues. no sense in spending $100 if its not needed.

 

I may very well do that, but my TPS is screwed...the plastic shaft that the connector slides over just cracked. So I'll be ordering parts either way. Ugh.

JEEZUS...I just called my local Mazda dealership, just to check, and this what they wanted for the following:

$156.77 Dashpot # N3A1-20-190.
$260.36 Throttle Position Sensor (NAPA $200)
$740.26 Brake Booster
$268.58 Dryer

The brake booster floored me, 'cuz I got a quote from Malloy for $431.79.

Ugh.

 

Oh, and yeah...I'm just going to put it back in for now. It's easy to replace, so I'm going to fix the fuel leak, test it out, and then once I get the price quotes from Ray, I'll decide on whether to replace it or not.

Thanks all!

 

you might try sourcing some of this stuff on the forum. Just make a WTB thread and see who has what. should be able to save alot of money that way.

 

Schweet! My dashpot needed adjustment!

It doesn't backfire anymore, it decelerates fine and doesn't die. It burbles a bit, and unfortunately the dashpot still needs replacement, as it's right on it when it's depressed...

But for once...once in a long while, the care drove like a champ! Great stuff!

 

Anyone have a engine pic showing exact location?

 

its on a bracket at the side of the the throttle body, just follow the inner curvature of compression tube to the throttle body and look down

 

This should help...

 

Do you have stock ECU, Power FC, what? Is your ISC valve still installed? deceleration behavior is controlled by a lot of different things working together.



the dashpot can be adjusted to correct idle sticking or idle stumbling problems. For stumbling problems, loosen the locknut and adjust the dashpot so that it makes more contact with the throttle. On a stock ECU there is also the idle adjustment procedure in the FSM (jumper the TEN terminal and adjust the bypass air screw). On a Power FC the idle speed and fuel cut settings affect deceleration behavior.