hi all.

I just bought a TII and I have a hesitate problem. When the boost start the car want to stop. he hang hard and some time I can go over 3000 rpm with no problem (very not often)

I have checked the boost sensor (at no boost I have 2.32V and at 8 psi 2.73V is it to high ?

To be shure this is the problem can I simply remove the vaccum from the sensor and cap it.

I just put some carb cleaner on hose and the motor doesn't change.

My BAC vavle isn't plugged too (I can't find the wire to plug in it ) This can affect the boost or the fuel map ?

does somebody have some idea of what can it be ?

thanx

chicoutimi

 

Is it 3000? or 3800?

 

from 2500 to 3000

if I rev it slowly the car seem to run well but if i floor it he hesitate very bad

can a bad wastgate operation can do this ?

thanx

chicoutimi

 

bump

 

sounds like a problem with the timing.
A bad wastegate will prevent you from boosting alot (you will boost some), but it will not contribute to hesitation.

Check your timing, and set your TPS first of all.
Start with that, and come back and tell us how that went

 

ok i wiil check this

thanx to reply

i think I found a first thing

I checked the Switching Actuator on the manifoald and he doesn't move.

I try to remove it and make it to move.

chicoutimi

 

ok I have adjust the tps to 1K (was 2.5K) for the idle and I have checked the timing. When I stay in fornt of the car the yellow mark is about 3/4 inch to the left. I don't know if this is correct. (i don't think so.

I have found my plug for the bac but the connector if finish. I have to find another one.

When I found the new connector I check to get the timing correct.

thanx

I will update my progress on this week.

chicoutimi

 

update ... I replug the bac valve (and he works well) I I adjust the tps too. But the idle he always to 1.5K. I try to play with the screw on the bac valve. to get the 1.5K I have to screw it at the maximum. if not, the idle is more higher. I spary the entire hose i can see with carb cleaner and seem to no vac leak.

My idle is bouncing now. As i adjust the tps the idle start to bounce

I think I can't adjust the timing as i not idleing well ?? is it true ?

I have check the variable resistor to see if it in range and i'm in the range. But probably that the old owner have play with this because it doesn't have the wax on it. I

I also check that the TPS has no step when I push it. it goes from 1V to 4.71V

I don't know what to do now ... Is it possible that the O2 sansor is out of range. I don't know what is the range.

I ear many pop in the exhaust.. it's probably do that I run to rich.

I thing the next step is to test the injectors ?

if you have any idea ... I take it ..

chicoutimi

 

^^

 

do the grounding thing
and if you have an 88 TII or lower set you TPS as per the Factory Service Manual with the check tool

 

i'll try to grouding thing...

could it be the pill thing ?

I think I don't have this pill n my boost pipe ?

thanx

chicoutimi

 

1. I don't know how, but you MUST get the idle below 1000 rpm so that you can set the timing. It appears to be way off. DO NOT try to set the timing with the rpms at the high level they are at right now.

2. If your hitting 8psi on a series four, then I think you hitting fuel cut. Do you have a fuel cut defender??? IF not....get one.

3. The switching actuator fails to the wide open position. So if it is not moving...don't worry about that right now. By moving I mean it should retract when the car is started up and not move again until the rpm is 2700 rpm, at which rpm it should retract.

4. I'd guess your high idle rpm is a result of the throttle stop screw holding the throttle plates open and or the throttle cable being too taut. It needs a touch of slack in it. Or the problem could be a air leak, maybe.

5. It could be the pill (orifice) or rather the lack of said part.

6. The pressure sensor...at idle, with the vacuum hose pulled off and plugged, the output from the pressure/boost sensor should be 2.3 to 2.75. That was at idle.

IF y0ur output from the boost sensor is just 2.73 at 8 psi boost......then there is something wrong here. Either you do have a fuel cut defender whose clamping voltage is waaaaaay tooo low, or the sensor is kaput. A fuel cut defender should be set close to 3.65 volts as the clamping voltage.

But if you have a fcd then the thing should be keeping you from hitting fuel cut because fuel cut does not happen until about 3.70 volts. So the low setting of 2.73 would be in your favor. That's IF you have a fcd.

 

Do not bother with your oxygen. It is not the problem.

Try that pill. Find an autoparts store. You want a pill. Or other name is restrictor orffice. Try that. Or somebody here could buy one and mail it to you. Where do you live?

James

 

I know this now I can't set the timing as long as I get my idle run below at 750 800 rpm. I can't find why my idle is messy like this.

Quote:

2. If your hitting 8psi on a series four, then I think you hitting fuel cut. Do you have a fuel cut defender??? IF not....get one.

No, I installed a mechanical boost gaquge and I stay to 6 psi or 7 max. When I rev the car a little bit the stock gauge went near 30 mmgh and the mechanical not move (0 psi). This is why I think the boost sensor is something weird. I don't have any cut fuel defender.

Quote:

3. The switching actuator fails to the wide open position. So if it is not moving...don't worry about that right now. By moving I mean it should retract when the car is started up and not move again until the rpm is 2700 rpm, at which rpm it should retract.

Ok, I have a freind with this this weekend and I checked the switching acuator and all look great now., It open I soon I start the car.

Quote:

4. I'd guess your high idle rpm is a result of the throttle stop screw holding the throttle plates open and or the throttle cable being too taut. It needs a touch of slack in it. Or the problem could be a air leak, maybe.

Where are the the stop screw on the tb. On the back of the tb I see many screw so I don't know what is what..

Quote:

5. It could be the pill (orifice) or rather the lack of said part.

Can I bought one from mazda ?

[QUOTE]
6. The pressure sensor...at idle, with the vacuum hose pulled off and plugged, the output from the pressure/boost sensor should be 2.3 to 2.75. That was at idle. [ /QUOTE]

I check that tomorrow.

Quote:

IF y0ur output from the boost sensor is just 2.73 at 8 psi boost......then there is something wrong here. Either you do have a fuel cut defender whose clamping voltage is waaaaaay tooo low, or the sensor is kaput. A fuel cut defender should be set close to 3.65 volts as the clamping voltage.

But if you have a fcd then the thing should be keeping you from hitting fuel cut because fuel cut does not happen until about 3.70 volts. So the low setting of 2.73 would be in your favor. That's IF you have a fcd.

I will chaeck that too..

wow.. now I have somethjing else to try..

thanx

chicoutimi

 

I think I found the problem with the boost sensor,.

I check it and he work very well.

2.32V at idle and 3.70 at 8 psi.

the problem ist the boost pipe. I plug apressur tester on it and I have a very bouncing pressure when i rev the car. that goes over 8 psi ont the pipe but my boost gauge don't move.

I have to found where that pipe came from and where I suppose to plug it ;;

thanx

chicoutimi

 

Yessssss I found the trouble. (I think).

I had a missrouted hose for the boost gauge.it was invert with the secound metal pipe that came from the rear of the engine( the middle one).

Now When the car run idle the mechanical boost gauge said 0 psi. but the boost pressure said 20 Vac. When I run the car when I pass over 3000 rpm both of the gauge climb. the mechanical one is at about 6psi and the stock about 25-30 mmhg.

I would like to know how the stock gauge should be at idle.I plug by boost gauge at the rear of the intercooler. is it a good place ? or I should the boost sensore pipe ?

I thing this is a good start..

is 6psi on a stock turbo is good ?

should I see my stock gauge to get hier that 25-30 mmhg ?

thanx

chicoutimi

 

^^