I just ordered a cheapie vac/boost to check my vacuum for leaks or whatever from glowshift.com. With that mentioned: What vacuum should I be at when the car is idling and be sure to mention what rpms. I already know that vacuum depends on rpm and that revving builds up boost, but what is a normal idling vacuum??

mott6904 wrote:..... then back prode the middle wire and see what it reads. If you rev the car up to about 2000 rpm it should jump around from 200 to 800 millvolts. If it doenst change at all then you have a bad o2 sensor.

Am I to be grounding to the chassis? If I recall right, I picked up a ground signal on the two outside wires on the harness side (unplugged). I am pretty sure of that because, iirc, I put the red probe on the battery pos to get voltage readings on the outside wires, so they must be grounds, right??

I am discussing gauge options in my other thread. Need some input on good combo wideband o2 sensor with a matching gauge.

--TJ

--TJ[/QUOTE]

s13_240_rb20 wrote:I just ordered a cheapie vac/boost to check my vacuum for leaks or whatever from glowshift.com. With that mentioned: What vacuum should I be at when the car is idling and be sure to mention what rpms. I already know that vacuum depends on rpm and that revving builds up boost, but what is a normal idling vacuum??

Am I to be grounding to the chassis? If I recall right, I picked up a ground signal on the two outside wires on the harness side (unplugged). I am pretty sure of that because, iirc, I put the red probe on the battery pos to get voltage readings on the outside wires, so they must be grounds, right??

I am discussing gauge options in my other thread. Need some input on good combo wideband o2 sensor with a matching gauge.

--TJ

I think on my car my vaccum is around -13 to -15 psi at around 850-900 rpm. I dont have my car hear to double check but it sounds right.If your 02 wiring is right all you have to do is put one probe on one end of the connector and the other probe at the other end. It should read 12 volts or - 12volts if the meter is hooked up backwards. If it doesnt then you dont have power or ground at the connector. I would then check to see if you have power at the connector. you do that by putting one probe on the chasis and the other probe at each end of the connector to see if you have 12 volts at one of the pins. If you dont have 12 volts at one of the pins then there is your problem. The 02 sensor gets its power from the ignition switch. Check pin 45 on the ecu to see if there is power there( the o2 sensor is spliced into this wire). If you have power then check the continuity at the other pin to see if there is a ground. The computer grounds out the heater so the key will have to be turned on. I hope i made this clear enough. Let me know what you find. As far a wideband kits carl had directed me towards wb02.com they have tons of different options i dont have one yet so i cant give you much info. on widebands

I will definitely start my next car-day by testing the output of the o2 sensor. Thanks. Unfortunately, it may be a few days. I will probably put the car on the proverbial 'backburner' until I get the vac/boost gauge delivered later this week. I just went out there to test it and the battery was dead again, so I decided to wait until I had the time to put some real effort into it...

--TJ

Might want to look into your fuel pump wiring while you're waiting...

Did you look to see how it was wired?

I'll try to go take a peek real quick...brb..

went and checked it out. I've got a wire run from the RB ecu (black/pink) to the engine bay KA brown plug (black/pink)...looks normal, but I guess I could shorten that wire a little bit....will do that when I go through rewiring for the new gauge and cleaning up old wiring.

As I mentioned in this morning's post, my car battery is dead again after two days. However, when I just went to look at my ECU pump wiring....I opened my passenger side door and heard a clicking from under my center console. I inspect and found that the clicking was coming from a box labeled "pass - constant - belt;; 12v" or some crap like that. I'll look again later. My first guess is that that box is triggered to power the sliding seat belts????? (the clicking sounded like a starter does when the battery was dead.....so I don't know if I should assume that this box is what I think it is, and don't know if that is sounding like that because the battery is dead).?????????? As always, it will have to wait until I have time for another "car-day".

--TJ

What wire did you tap into inside the fuse box for power to the RB harness?

Have a friend with a multimeter check the voltage at the pump WHILE you are cranking the car... let us know what you find

Check the voltage on the batt... if it's low now there might not be enough power for the seatbelt to function which might cause the noise

ive checked it....stays steady at 11.8v

Hey man. You definitely have a bad 02 sensor from my readings. Mine does not in the least stay steady. I get a steady fluctuation on mine, which like we mentioned, should be happening. There's no way a car can sustain and equal 02 reading across the the rpm range, or even idle for that matter. Replace and move on.

o2 sensor is not a primary sensor...it is only used for fuel trim...nothing else; will not affect your starting and driving problems.

Do you have voltage to the two outside wires on your o2 sensor? Thats the heater. Mine was not working at one point and ran like dookie.

Evan

90_rb20 wrote:Hey man. You definitely have a bad 02 sensor from my readings. Mine does not in the least stay steady. I get a steady fluctuation on mine, which like we mentioned, should be happening. There's no way a car can sustain and equal 02 reading across the the rpm range, or even idle for that matter. Replace and move on.

you looked at your Datascan readings? please confirm...mine was steady at 33, just wanting to make sure that you are testing the same way. What is the part number of a wideband o2 sensor I should get. I don't want to order something (like a bosch) and find out I got the wrong one.

240z4u wrote:Do you have voltage to the two outside wires on your o2 sensor? Thats the heater. Mine was not working at one point and ran like dookie.

Evan

I read voltage on the 2 outside wires only if I put the red probe on the battery POS side...is that what you mean??

240z4u wrote:No, fuel pressure was fine. It was a vac. leak from the injector Orings.

Sounds like you have a dirty fuel filter or a dying pump.

Evan

I know that my pump was suggested before, but here is what I have done today. I took my pump out and put a 13.75v power source to it, while cycling gas with injector cleaner. The following 4 videos are in order and I'll make notations to anything special...

pump starts out fine when turned on..http://s268.photobucket.com/al...9.flv

pump slows down greatly but will still build pressure to my fingertiphttp://s268.photobucket.com/al...2.flv

pump gains significant power when removed from gas (kinda expected, since air is lighter than gas???)http://s268.photobucket.com/al...3.flv

pump only trickles after that....http://s268.photobucket.com/al...4.flv

sounds like I need a new pump eh?? Silly me thought the pump was fine, and maybe just had low voltage. But it pumps weak at 13.75v unless removed from gas. Do you guys think my pump has crapped out or does it look like it is working just the way it should?? It is a Bosch 040. Should I go with another Bosch?? Walbro?? I've tried em both...which one is more reliable and can get the job "done"??

--TJ

IMO that pump is junk, It doesnt look like its pumping hardly anything in a few of those video's and the ones it is pumping its extremely weak. So I say invest in another pump.

My Walbro does fine. It might be the cheapest alternative.

fuel pumps are postive displacement pumps...you need to have resistance in order for the pump to build pressure.

I know it needs resistance for it to pump but that is barley spitting?

Im not too familiar with the Bosh pump, But my walbro will pump hard with the line off, Not pressure hard but it fills the entire line. That bosh is doing good to drip LOL

Carl H wrote:fuel pumps are postive displacement pumps...you need to have resistance in order for the pump to build pressure.

But as you can see, it pumps slow and builds pressure slowly. Shouldn't it be pumping more than that (as the others say) even without resistance? I guess I am just thinking about the walbro's I have had that would even arc out 3 feet...

--TJ

You should have a power and ground on the 2 outside pins of the 02 connector if the only way you get it to read is connect the red probe to positive battery terminal then there is another problem. you are not getting power to the o2 heater and possible pin 45 on your ecu which is the ignition switch wire. The reason im saying pin 45 is because it also powers the o2 heater. Check to see if you have power at pin 45 on the ecu if you do then add 12 volts to the correct pin on the o2 connector. If you dont have power to the heater then your o2 sensor isnt getting hot enough to measure the gas correctly. Which is why it is not changing at all. You might have a bad o2 you might not but if the heater not getting power then you are going to have to drive the car for a while to warm up the sensor enough to get it to work. A bad 02 sensor will not keep it from running but if your not getting a switched 12 volt signal to pin 45 on the ecu then it wont run. so go ahead a check all of that see what happens. either your heater isnt wired in right or you dont have power to pin 45 or you dont know how to use a multimeter.

Did you check to see if your pump is getting voltage while you crank with the pump in the car?

If for some reason you do actually need a pump... get the Supra MKIV denso pump... flow is very good and it's quiet

rbsileighty wrote:Did you check to see if your pump is getting voltage while you crank with the pump in the car?

If for some reason you do actually need a pump... get the Supra MKIV denso pump... flow is very good and it's quiet

ya, pump voltage stayed steady at 11.8v during cranking. I probed the wire harness for voltage (and could hear it running) and turned around to watch the meter during cranking..

--TJ

Did you get the problem sorted?????