Auto Drivetrain Question

[Spanky_DSM]

I understand these cars are heavy but im asking this as a process of elimination.

My car feels extremely slow at cruising speeds, its feels like i'm pulling a car behind me.

My question is when in Drive, upon releasing the brake should the car start to creep forward? Mine doesn't and am suspicious of driveline drag.

Thanks.

 

[91-GS]

From my experience the car will move with brake released and engine at idle.
Have you checked the brakes to make sure they are not dragging?
Checked tranny fluid? (Trying to think of the easiest solutions first)

 

[Spanky_DSM]

The tranny fluid is nice and freshly topped off.

I havent checked the brakes but will inspect the calipers, its time for a brake change any how.

This car honestly feels slower than my old 420a when not in WOT.

ill be driving and even going into boost, lets say, 5 or 7 psi and its barley even inching forward.

EDIT: i forgot to add i flushed the transfer case when i fixed my rod bearings, so clean fluid on that.. rear diff was flushed about 3 months ago but even when having fresh fluid this problem was still there.

 

[91-GS]

What about revving her in neutral? Everything good there, or does she seem sluggish?

How did the issue start? Was it sudden, or came in over time?

 

[Spanky_DSM]

Revving is normal, WOT it pullled pretty nasty at 20 psi during the moment i had my evo injectors installed.

I have a good o2 sensor, Air fuel ratios are in check during open loop.
I am getting horrible gas mileage tho.

Im thinking its a Spark issue maybe.

Any other suggestions would be wonderful.

 

[91-GS]

If you think spark might be an issue, unplug the plug wires (one at a time) and see if anything changed. If you unplug one, but she still runs like before means you found a bad plug/wire. Pull the plugs and inspect them as well.

Although won't spark/fuel issue throw off the air/fuel ratio since there will be unused fuel in the exhaust?

"Check Engine" light is off, right?

 

[Spanky_DSM]

Very true, Im running the ngk plugs. I might try some alternatives.

Check engine light is one, but its throwing a code for EVAP system which i deleted.

Zero boost leaks, with the exception of a bit of crank case pressure being recirculated back to the intake.

Possible retarded timing? I dont have a hold of a logger but currently hoping a guy i met can log my ecu with dsmlink.

Tho my ecu is not chipped i heard it will still log at a very slow rate, but hopefully enough to check timing degrees.

 

[DSM1G90]

True, pull a plug and see the color of the porcelain - white=hot, light tan=normal, and black=rich.

I'm pointing to a rich setting...why your mileage is horrible. Got a cold t-stat, like a 160 or any below the required 195 being used where this will throw off the A/F ratio set by the ECU since the ECU is programmed for a 195 T-stat?

But, no creep on idle in D is a wonder - wonder if the filters in the tranny are getting plugged up. What fluid are you using ... and hope not Dextron, for that will kill a DSM tranny in a quick.

 

[Spanky_DSM]

ATF 4 for the tranny fluid.

Perhaps a clogged filter you said? Im more than sure the filter needs replacing. The fluid is new, only because it was topped off from a seal that spilled everything but i never serviced the filter.

I will post up pics tomorrow of all 4 plugs.

 

[crash89]

Or you're looking into it too much and one of your brakes are hanging up. Does the car pull to one side or the other? When you let off the gas do you slow down a little faster than you should? Cruise for a bit and put it in neutral, do you slow abnormally? Any smells? After a drive are any one of the brakes hotter than the others? All signs of a brake hanging up. Thats where I would start anyways.