Does anyone know or whats your best guess as to what negative symptoms would happen if the vacuum hose from the bottom of the BPT valve was disconnected from the EGR tube going around the side of the intake manifold?

Idle issues?
Emissions issues?

Steve

I capped all that off a long time ago and never looked back.

My idle improved, but I can't speak for emissions. There aren't yearly inspections in my state.

On the high port cars at least, the EGR is independent of any ECU readings or control. Install a few vacuum caps and the car is none the wiser. :cool:

Originally posted by JimR


On the high port cars at least, the EGR is independent of any ECU readings or control. Install a few vacuum caps and the car is none the wiser. :cool:

Actually I don't know if that is entirely true. What controls the opening and closing of the EGR and AIV solenoids? It must be a command from the ECU.

Steve

The BPT valve is one of the things that control the EGR valve. The EGR valve opens when It receives vacuum pressure from the BPT valve (Back pressure transducer) and when there is positive exhaust pressure on the bottom of the EGR valve, So if you remove the BPT valve, your EGR valve will no longer work.

No solenoids.

The AIV, EGR and BPT are all mechanical, meaning there are no sensors, no ECU input or output. Remove the AIV, cap off the EGR and BPT and enjoy a much simpler engine bay. OBDII cars are different and I believe will throw a code. On emissions day, simply reinstall the vacuum line on the EGR and BPT. Your car will NOT run rich or suffer any adverse effects.

according to JWT certain models I think after 92 and all california cars have a sensor hooked up to the ECU mine has it and it looks like a very small two wire O2 sensor its on the EGR pipe on the intake manifold, or atleast mine is, when you get your ECU tuned from JWT that put something over the circuit for that sensor or atleast thats what Ben from JWT told me...I now cause they have my ECU right now for my Turbo Program...well got to catch the bus....oh yeah when I disconnected mine it idled i little weird but not that noticeably

Originally posted by NismoPC
No solenoids.

I'm not sure if you were referring to later model cars (of which I am not familiar with) but the B13s definitely have an AIV and EGR solenoid which is controlled by the ECU. There is a trouble code of 32 given if there is a problem with the EGR solenoid.

Steve

Originally posted by thepep


I'm not sure if you were referring to later model cars (of which I am not familiar with) but the B13s definitely have an AIV and EGR solenoid which is controlled by the ECU. There is a trouble code of 32 given if there is a problem with the EGR solenoid.

Steve

Hmm? I had a '91 NX2000 and the EGR valve and BPT valve failed on me. I nippled them off for a while then I cut out a template from aluminum and completely blocked the EGR valve. Never had a EGR solenoid code or any engine codes appear. That car had 124,000+ when I sold it. The buyer replaced the EGR and BPT I beleive. He sold it and I think it now has over 140,000+.

Code 32 is:
1984 through 1986 EFI models; check starter system. All other models: EGR malfuntion (California models)
EGR control valve does not operate.

That didn't state anything in regards to a EGR solenoid code, but that the EGR valve is malfunctioning on Cali models only. I can only assume that the ECU is able to detect incorrect or improper vacuum somewhere else that received the vacuum from the EGR/BPT valves and causes the ECU to blink that code.

Is your car from Cali?

We did a cam install on my 92 and we removed EVERYTHING fromt he front. the AIV, the oil seperator, the motor looks so much cleaner! All i need is the bung ;) for the AIV in my header, and then i can lose the pipe as well. I cant tell you how the car is running, i still need to play with the timing on the S4s that just went in..:D

so i can take that little black hose off the bpt, and plug it? and plug the egr too? no emission testing here... i have a high idle and a little hesitation to 3K... would it be effective?

Originally posted by NismoPC


That didn't state anything in regards to a EGR solenoid code, but that the EGR valve is malfunctioning on Cali models only. I can only assume that the ECU is able to detect incorrect or improper vacuum somewhere else that received the vacuum from the EGR/BPT valves and causes the ECU to blink that code.

Is your car from Cali?

No, it is a Federal car. The AIV solenoid is above the throttle body and connects to three things. The EGR solenoid is below the intake and on top of the tranny. It also has three connections. I don't have my FSM in front of me right now but I read earlier this morning that the ECU uses other sensor inputs to determine when to open and close both solenoids.

If the EGR solenoid wasn't touched along with the vacuum lines, its possible that a trouble code wouldn't be given since the solenoid is opened/closed by other sensory inputs. Disconnect the EGR solenoid connector and see if you get a trouble code. My guess is you would.

Steve

i just want to make sure exactly which hose you need to block off to disable all that crap. is it just a short hose from between the egr and the bpt?

Here is a link to a picture of my brother's car, that has the hose disconnected:

http://www.xxiii.com/wcox/se-r/1%20destructive%20little%20fuck.jpg

The main thing to remember is that you need to plug or cap the vacuum line. He has his plugged with a golf tee in this picture. I did this, until I got the chance to get a rubber cap from autozone. I just removed the hose and installed the cap. It makes it look a little cleaner :)

-Colin
'93 NX2K

is it just me or is there a hampster in your engine?

Originally posted by jbloggs_c
is it just me or is there a hampster in your engine?

LOL! I didnt notice that untill you said something!:D

Hamster, thats a fukin rat dude


I'm going turbo soon, so i guess i gotta take mine off since the manifold probably doesnt have an egr opening, might as well take it off now =)

I did just as shown in Bud Man's pic (except for the mouse), and my car runs better. I plugged that line w/ a golf tee also - it is temporary. Before I had a slight hesitation about 3k rpms, and it is alot smoother now. I have a pretty recent tune-up, so I don't think my hesitation was from other items except for the EGR. Since it is so easy to unhook and plug it is defenitly worth trying if you have a hesitation.

Josh

i cut the hose in the middle of the ERG and BPT valves and put screws in both ends , earlier this evening my car pulled a code , i think it has 2 do with the second O2 sensor ,(its older than dirt.) Did any one have this problem with their cars after the hoses were blocked ...

I unplugged the hose long ago and plugged it with no bad effects. I still have no codes on the engine at 168,000 miles or so. It pulls as hard as ever.

Brent