DHP PCM question

[ATL99GT]

I am not too familiar with the way this PCM works or how exactly it will help you... I read the features it offers and they sound good, but I am wondering how it effects things such as drivability, gas mileage, transmission actions, etc. And how easy is it to install one in my driveway? Are there any other parts than just the PCM that would need to be purchased? Thanks.

[tejohnson]

No, just the PCM. It is as simple as disconnecting, and re-connecting the new. You will need a 7mm socket.

You will need a higher octaine gas.. GIven you have a 99, make sure to go over the car well and look for signs of trouble. I would also recommend swapping out a majority of the sensors and having the injectors cleaned... But, this is my opinion... These last comments are only suggestions, not requirements.

[coupe]

Dude just buy it and slap it in.
Its just plug and play.

[AaronGTR]

Search... ton's of info on this already.


It's basically a 30min job or less to swap the pcm's and get it running again. Drivability and gas mileage are typically good although you do need higher octane gas. The transmission programming is one of the best features and is worth the price by itself. It makes the car much easier to drive aggressively without having to floor it all the time to get it to shift the way you want.

[alerored04]

pfyc also suggests swapping to a 180* tstat, i did, im not sure how necessary it is though.

[drumking1721]

uhh i disconnected my battery yesterday for a while to install new gauges. Now the tranny is shifting crappy, I mean the fan still turns on after i shut the car off,but the shifting i really weird,will i have to take is back to have the case learn and crank procedure done again that DHP says? i really dont wanna pay another $85

[tejohnson]

No, you don't need another CKP learn done. This only needs performed it you:

-Get a new PCM
-Replace the 24x sensor
-Replace the harmonic balancer/pulley

You could have 35 PCM's, where you have a case learn done with each, and you coulld swap between them without any problems.

The shifting is more of a concern. The transmission adaptive whifts were cleared, and your PCM is relearning the adaptive shift tables. This takes a bit of time, but you shoulda experienced this when you got the DHP PCM in the first place. If the shifting is really bad, it may be a sign of a mechanical pressure problem...

[coupe]

uhh i disconnected my battery yesterday for a while to install new gauges. Now the tranny is shifting crappy, I mean the fan still turns on after i shut the car off,but the shifting i really weird,will i have to take is back to have the case learn and crank procedure done again that DHP says? i really dont wanna pay another $85


Since you disconnected your battery the PCM now has to relearn your driving habits.

[drumking1721]

k thanks guys,ive been worried

[coupe]

Like what H.O.Driver always says to me," Just needs to relearn ass-hole driving".

[drumking1721]

:jackson

[Blight]

In my opinion the DHP PCM is the best mod i ever got !

ALSO I SUGGEST hold on to your stock PCM i have found it to come in handy a few times. Especially if you plan on doing major mods, you dont want to overwrite your 300 dollar DHP PCM and then not have anything to fall back on when the mod breaks ;) ya know

[coupe]

Thats why i kept mine.

[drumking1721]

yea....there only $99 on pfyc now. And my shifting is still weird. Its only first.its like the tranny isnt catching up the shift points,its not skipping or anything,its just when you accelerate hard....hmmm i want my car to be back....i beat GP's with that thing,no joke

[coupe]

You mean GP GT's....
How long have you had it?

[drumking1721]

I got the PCM back in march

[drumking1721]

and yes, GP GT's...back at school some guys have modded GP's and i race them

[coupe]

How long has it been since your battery was disconnected?
Is it just lagging getting into 2nd? If thats the case its not the DHP causing it.

[drumking1721]

I unplugged it last friday when i did my gauges. I had no tranny problems prior. Its just you accel hard and the RPM's go to the 5800 like its suppose to,but it sounds like it cuts out b4 that,i mean i lost some Transmission fluid,could it be that? i went to autozone last friday night and put a quart in,should i put more? I just have a feeling its something with the PCM.

[coupe]

I have a feeling its something else.
Was your tranny fluid low?

[drumking1721]

yea.............when i took out the little valve thing to put my sender for my gauge in some leaked out. I drove it to auto zone after and got a quart of fluid. Idk it just seems like the pressure isnt there....

[coupe]

you shouldnt have lost more than 1 shot glass worth............if that, you shouldnt have lost enough to add any.
Hopefully you dont have to much tranny fluid, which is what its starting to sound like.

[drumking1721]

I just went out for a ride to the cell company. Shifting is better thank god. I just dont get why it took so long. I dont remember it taking that long to begin with

[coupe]

It takes a few hundred miles for it to relearn your driving.
The first time you where used to the old PCM tuning and the DHP, even though it hadnt learned yet, was still vastly better than the stock PCM tune. Thats probably why it "seemed" it didnt take long.

[atc3434]

Mine always took a while to relearn when I'd reset the computer. I'd always think the tranny was finally letting go, but a week later it would be shifting like a shiftkit again. Don't add too much fluid, that can be as bad as not having enough.