donny

My air pump is taking a dump, if I remove it and the cat will this cause a problem with the stock computer... We have no emissions testing in Minnesota.

Heath

iTrader: (11)

Nah, you just need to wire in a 330 ohm (I think) resister to keep the ecu from throwing a code. I'm not sure if there is any type of adverse effect elimination will have on your cat but of course emissions will suffer as you already stated. You can use a 4 rib belt if you can't find a 5 rib in the correct size. I think it's somewhere around 30" but don't take that as fact. Best of luck!

poss

iTrader: (5)

Serious problem? NO
You will run a little rich at idle though because the air pump is not feeding additional air to the combustion chanber.

poss

iTrader: (5)

No resistor required

supracosworth

Combustion chamber?? It feeds to the cat only doesn't it?

bureau_c

Nope, I'm not sure why but it definitely does more than just pump air to the cat...at a minimum the idle will be affected. I'm not sure about anything else.

jds

rynberg

You should definitely NOT remove the cat while still running the stock ecu.

The air pump directs air to the intake at idle and to the cat during low rpm operation.

If your air pump is bad, just buy a used one from someone on the forum. They are for sale all the time in the classifieds section.

FD Racer

If you remove the cat and the airpump you'll be okay...but you might get boost creep and/or spikes...which is a recipe for disaster with a stock ecu. As someone already mentioned, your idle will be effected if you dont run an airpump. How do you know the airpump is going bad?

striker

What about if the airpump is removed with a MP and a PFC? Will the idle still be rough?

RX7 RAGE

iTrader: (22)

Idle will be fine if you remove airpump and you put in a pfc and mp at the same time. I did that myself.

striker

Alright thanks
So that means I need a 295K4 belt since the 30" 5 rib belts dont seem to exist?

dubulup

If you you are removing the AP, you should do it right, which includes removing the cat and getting a Hi-Flo (or mp) and removing the Secondary air injection (and the two solenoid valves that control it, which will need resistors)...

As stated before you will run rich at Idle, because the SAI isn't pumping air into the LIM...so you will need some sort of ECU that you can lean out the idle fuel.

just my opinion...

Cihuuy

secondary air injection?? which one is that??

and which 2 solenoid controls the airpump??

I disconnect the AP and gutted the cat, and now my idle went up to 1400rpm.. is it normal?

dubulup

Normal? I'd say a 1400rpm idle isn't normal.

Secondary Air injection is referring to the whole system (what people refer to as emissions crap) The ACV (air control valve) is part of it. Contraption that is on the LIM, has two vac lines attached to it. The Solenoids that control the ACV are, relief 1 and switching, it determines where the secondary air is injected, LIM or cat.

Unbolt ACV and install block off plate, pull solenoids and install 330ohm 1/2 watt resistors, remove airpump and cat (might as well get rid of the plumbing also)...lean out idle fuel map. (might need some idle air bleed screw adjustments too)

hope this helps.

Cihuuy

thats what i did! i did the symplified seq setup, i remove all the emission crap... hahaha install resistor and BOP. now, i disconnected the airpump and got the car running. Rpm goes to 1400... if its not normal, then how to remedy this?

dubulup

try adjusting the air bleed screw...

maybe TPS adjustments? But I don't see why you would need to adjust it.

Stock ECU???

Cihuuy

yup yup... stock ECU

I took the turbo out, port the wastegate, remove LIM, change the all the gaskets and all the vaccum hose!

Air bleed screw and TPS adjustment... got it... but how to adjust it? by feel only? tanx again

dubulup

TPS Adjustment...
Tools Needed:
(1) A high impedance voltmeter (preferably a digital) with one
alligator clip.

(2) A small safety pin opened up to form a 90 degree angle.

(3) Depending on the type of fasteners that hold your TPS in
place; the tools needed to loosen and retighten them. Mine
had bolts with a combination Philips screw driver and 7MM
nut head. Some have only a screwdriver head and need a 90
degree bend screwdriver or screw driver tips for a ratchet drive.
These screw driver head only bolts are the pits and most owners
have replaced them after removing the throttle body.


TPS Connector Leads (4 lined up vertically) and Required Voltages:
(1) 2nd from top (green wire with red stripe), this goes to the
3F ECU connector. Closed throttle +V range is 0.75 to 1.25.
Fully opened throttle +V range is 4.8 to 5.0.

(2) Bottom (black wire with green stripe), this goes to the 3G
ECU connector. Closed throttle +V range is 0.1 to 0.7.
Fully opened throttle +V range is 4.2 to 4.6.

Procedures.
(1) Start and run engine until at normal operating temperature
and the fast idle cam is at normal idle position.

(2) Turn off the engine.

(3) Remove the AWS hose that connects to the throttle body
curved inlet pipe and to the AWS solenoid behind the throttle
body. This is to give you easier access to the TPS bolts.

(4) Remove the hose from the MAP sensor on the firewall and tuck
it down out of the way. This also gives you more room to access
the TPS bolts. If extra room is still needed, remove the MAP
sensor from the firewall.

(5) Totally loosen the bottom TPS bolt and partially the top one.

(6) Connect the negative volt meter lead to a good ground point.
I used one in the diagnostic connector since it goes to the
ECU.

(7) Insert the safety pin point into the TPS 3F or 3G connector
between the rubber weather seal and the wire. Using the
alligator clip, attach the positive voltmeter lead to the
safety pin head. Select the appropriate voltmeter range.
Be sure not to accidently groung this lead!

(8) Turn the ignition on without starting the engine.
If there isn't a voltmeter reading, adjust the safety pin until
it does have a reading.

(9) Record the voltages for closed and fully opened. Open the
throttle fully by hand, not the accelerator pedal.

(10) Do the same for the other TPS connector point.

(11) If any of the four voltages are out of range, loosen the
top TPS bolt and adjust the TPS until all four are in range.
If all four can't be adjusted correctly; then either
the TPS is bad, the fast idle cam is still engaged, or the
idle set screw on the throttle is way off normal position.

Air Bleed Screw is the screw near where the throttle cable goes into the UIM, loosen the nut and turn screw clockwise and idle should increase and the opposite for lower, refer to the WSM for propper procedure.

But from your list (vac lines), it could be a number of things causing high idle...

Cihuuy

hmmm... thats a long post dude... but very informative... i dont have a voltmeter yet, time to get one

I should have change the those philips bolts!! it will make work much easier... tanx dude

bureau_c

Hmmm...I've removed the airpump relay because my pump sounds like I've attached a coffee can full of nuts and bolts to the pulley when its running, and I don't want it seizing or worse and screwing up something else. I figure my cat is so old its days are probably numbered anyway. If I get around to it I'll get another air pump and put it on, if not...I guess I'll end up getting a hi-flow cat at some point. Anyway the point of my post...my idle actually dropped, and has a tendency to oscillate a little faster than once a second or so now. If I turn off the AC it is dipping probably to 500 or so. I don't know why yours has kicked up to 1400, but that's not what mine did when I stopped running the air pump.

jds

dubulup

I didn't write it...I guess I should have posted a bibliography...I pulled it from Rob or Wade's site...can't remember.

striker

the other reason the car runs bad at idle is that the airpump feeds air upstream of the o2 sensor. so the o2 sensor thinks everything is fine. but when you remove the airpump, it believes conditions have richened and therefore cuts fuel, even though nothing has really changed. this causes the lumpy/hunting idle.
i believe this is what is happening, anyone confirm it?

Cihuuy

Bureau c: that's what im trying to find out meself. Oh wait a minute, would removing the double throttle butterflies would increase the rpm? it has been 4 months of on and off work on my car... and im getting older everyday so forgive my lack of memory...

sori to go off line tho... you may all continue...

Dubulup: well, tanx anyway for posting it.

dubulup

I think I'm reading this right...

The O2 is taking a reading in the exhaust, so what you said is not correct. The O2 would see the change, the AP puts air in the cat during light load/low rpm driving. At idle the AP is directing air to the ACV (LIM). So, the O2 will see the change.

Cihuuy - removing DT might lean out the A:F a little at idle when cold (due to the air flow thru all ports not just one), but I can't see that being your gremlin.

striker

no, but the airpump i believe is also adding air upstream of the o2 sensor; in the manifold. i believe the ap directs air to 3 places. the cat, acv, and the turbo manifold. when you remove the extra air going to it, you increase the concentration of hydrocarbons in the gases, making it richer. i think i read something on this a while back. just trying to confirm it as i also want to chuck the ap without disrupting idle, or if there is a way to tune out the problem.

to add another thing. i may be wrong, but the hose going into the center of the turbo manifold on the passenger side, is it connected to the ap? i think i tracked it back to it, but i am not sure, what it's function would be.