1.4 Cj Stepper Valve And Lambda Issues

[CRM 0]

After some advice pls on this K plate 1.4 cj with the single point FI.

the stepper motor is not working correctly and seems to take an age to return to idle. i presume this can be replaced, if so any recomendations from where ?

also above the fuel guage there is a warning lamp which looks like the cat light or FI warning, again i am presuming this is the lambda sensor at fault ? can perform without fault for ages then without warning the light will come on, and the fueling goes out of the window and causes the car to judder quite a bit. then 10 seconds later will clear for another 20 miles or so, again if anyone can confirm this is the problem and symptom i would appreicate it

Can the cat be binned and the lambda be bypassed ?

 

Cheers in advance

[snillet 1]

After some advice pls on this K plate 1.4 cj with the single point FI.

the stepper motor is not working correctly and seems to take an age to return to idle. i presume this can be replaced, if so any recomendations from where ?

also above the fuel guage there is a warning lamp which looks like the cat light or FI warning, again i am presuming this is the lambda sensor at fault ? can perform without fault for ages then without warning the light will come on, and the fueling goes out of the window and causes the car to judder quite a bit. then 10 seconds later will clear for another 20 miles or so, again if anyone can confirm this is the problem and symptom i would appreicate it

Can the cat be binned and the lambda be bypassed ?

 

Cheers in advance

 

I saw that you got no good response to this one.

You have the TU3M engine ?, what year?, is it one with the Bosch Monojetronic A2.2 system ?

 

If so, it´s likely that you have a fault in the idle switch which is incorporated in the idle motor assembly.

It´s a VERY common fault on the Monojetronic systems, when it´s faulty the ECU doesn´t know when you´ve lifted the throttle.

A properly functioning A2.2 system should when you "blip" the throttle a little, do a small "blip" movement with the idlemotor when the throttlearm touches the top of the idlemotorpin.

 

You should easily be able to read out fault codes on that system though.

These systems are generally quite easy to work on, very simple stuff for being EFI.

[CRM 0]

You are a gent, and thanks for taking the time to respond to a newbie. its quite a wierd thing on some forums, and i have seen it on 2 of my own bike forums, that newcomers are avoided for a bit until trusted. strange culture in forums.

 

Yes its the TU3M engine, and its a 1993 registered car, but am sure its a 1992 crossover build, not sure which FI its using but is the pretty simple basic one.

as for the stepper motor, i presume this is the idle motor and the thing that makes the throttle go from under your foot ? i can feel the throttle disapear for no reason when the FI light comes on and it starts to judder.

I think we have a winner here with the fault, as i was advised that the stepper motor has a problem.

 

Ok next step, where can i get one and what is its proper name ? if anyone has one in good order for sale please do let me know, or a link to ebay or anywhere would be most helpfull

Cheers

[RossD 43]

I think a local Bosch fuel injection place would be good bet, if not it may be worth asking your local factors if they knwo of anybody local.

 

Of course if money is tight there is always the breaker yards, remember that this fuel system was also fitted to the 106 and 306's too so that should help widen you're search!

[snillet 1]

You need to make shure what kind of engine management the car has if i am to help you out with this. Since it´s as new as 92/93 it could also have magneti marelli G6 or a motronic system. Just read the label on the ECU, if it doesn´t say, reply back here with the number on the ECU and we´ll know what system it is.

 

If it is the monojetronic A2.2 it´s VERY easy to do simple faultcodereading and fixing on it.

 

And BTW, i´m not really that much on this forum, just occasionally when i want extra info on things, your thread came up when i searched for something else. The monojetronic system is VERY common on a lot of cars from this age in countries like Sweden/Germany/Switzerland and some others, where cathalytic converters where required by law since the late -80:s.

[mhyphenl 10 1 Cars]

I think a local Bosch fuel injection place would be good bet, if not it may be worth asking your local factors if they knwo of anybody local.

 

Of course if money is tight there is always the breaker yards, remember that this fuel system was also fitted to the 106 and 306's too so that should help widen you're search!

 

 

Hi there,

 

I have a throttle body from a TU3M engine, the motor and the injector are in good nick, the throttle position sensor is a little worn though. Best bet would be to swap the stepper on to yours. Bear in mind though that on these systems the coolant temp sensor is also instrumental along with the lambda, air temp sensor and throttle position sensor in getting the correct mixture. The K light will come on if any of these things are reading incorrectly. PM me if you need anything.

 

Cheers, Martin

[CRM 0]

Hi there,

 

I have a throttle body from a TU3M engine, the motor and the injector are in good nick, the throttle position sensor is a little worn though. Best bet would be to swap the stepper on to yours. Bear in mind though that on these systems the coolant temp sensor is also instrumental along with the lambda, air temp sensor and throttle position sensor in getting the correct mixture. The K light will come on if any of these things are reading incorrectly. PM me if you need anything.

 

Cheers, Martin

 

Martin, cheers, and if you want to work out a price for the sensor and any spare sensors you have too which i can swop / try then that would be superb.

I dont suppose you have a good gearbox do you too ? this CJ has one fitted from something else, and revs its spuds off at 80 flat out, and just doesnt feel as broadly geared as her early G plate CJ and also the thing pops out of gear if not on the gas turning corners too which is a pain

I would post in the wanted section but need to post far more gibberish before i am allowed