wanarace74

hey i had a buddy say if i remove my smog pump i have to have a upgraded ecu. is this true? anyone here removed the smog pump and been fine? please let me know

Mahjik

iTrader: (1)

You don't need a new ECU, however, the stock ECU will be looking for it and will probably cause idle problems. You can simply raise your idle high enough that the car won't stall if it becomes a problem. Otherwise you have two options to try:

1. Putting a resistor where the airpump used to be to trick the stock ECU (not sure if this works but I can't see why not).

2. Aftermarket ECU

rynberg

There is no point to removing the smog pump unless you're running a midpipe, at which point you should have an aftermarket ecu anyway.

rynberg

Chris,

I wanted to respond to your PM in a public way.

IMO, you should NEVER run a midpipe with the stock ecu. There is just too much of a chance for boost spiking or creep to risk it. It is not safe to boost over 10 psi on the secondary with the stock ecu. If by some means you can control your boost to 10 psi with NO SPIKING, then you are safe, but most people find that impossible.

At the very least, get a Pettit ecu for the car. They are only $400-$450 used and will make the car much safer to run a midpipe with.

SleepR1

Agree with rynberg. Don't even think of doing a midpipe (full open exhaust) without an ECU replacement or at least an ECU upgrade.

bureau_c

The ECU isn't really looking for it, it just assumes it is there and goes about its business accordingly. I don't using a resistor would help...the ECU doesn't really detect the pump, it just applies voltage to a relay which activates a magnetic clutch, much like the one on the AC compressor. Not having it will cause idle problems, at least when cold, but I never had a stalling problem because of it....however, it really did seem that the car wasn't as drivable under partial throttle. I can't really explain it, but it seemed a bit sluggish to respond to throttle changes, etc. during around-town driving. The car ran much better with the air pump, when the stock ECU was present.

jds

Mahjik

iTrader: (1)

lmao..

Did you just read what you typed?

Obviously, there is something the stock ECU is doing when the airpump is there. If it wasn't the car would run just the same without it (which isn't true as you just stated). I did disable my airpump for a trip to test where I had noise coming from and I did experience stalling problems the more the car drove. That's mostly depends on where your car nomally idles though, as mine idles normally 700-750rpms. If your car idles higher, then disabling/removing the airpump might not cause stalling problems on the stock ECU (as I stated above with raising the idle).

Just because the ECU doesn't throw a code when it's gone, doesn't mean it's not using it for something.

bureau_c

If it could tell the air pump was there don't you think it would modify its behavior accordingly? The car runs differently without the air pump precisely BECAUSE it doesn't know the difference. It is acting as though the air pump will be routing air in one of two or three directions, and when it doesn't, the car doesn't run the same.

Think about it. What is connected to the air pump? There's a voltage and ground applied to a magnetic clutch. There are NO other electrical connections, and this is coming off a relay. The ECU itself is just triggering a relay. How is it supposed to know the air pump is there?

jds

Mahjik

iTrader: (1)

lol, the stock ECU hardly modifies it's behavior for anything (aside from limp mode or not), why would it do it for the air pump? What's it's going to to do, throw itself into limp mode just for the air pump?

Regardless of whether the stock ECU knows about the air pump or not (and I don't think either one of us can honestly answer that), there are problems associated with disabling/removing it and using the stock ECU and the only means of taking care of them are the same means provided in my original post.

bureau_c

I agree with everything you said save the part about the resistor. In fact, in your post you said you didn't know if it would work but you didn't see why not. That tells me you haven't actually tried it...I don't see how it could possibly work, since the airpump connection is just used to activate the clutch. Unless I totally missed something in the schematic this isn't connected to the ECU directly at all, and if it were, the only purpose that would seem to serve would be to allow the ECU to throw an error code, which it does not do. Now, if I misread your previous statement and you have in fact tried the resistor, and it actually appeared to have an effect...well, I'd be very surprised because it doesn't make sense to me.

jds

Mahjik

iTrader: (1)

An easy way to test would be to unplug the air pump, and then give it it's own power source to see if the normal idle problems still exist.

JONSKI

I have no airpump, a gutted main cat, and the stock ECU. I've also gotten rid of a few other things (check sig). I had to up my idle a little, though.