My 245 TIC has a starting issue... After sitting for a few hours when I go to start it it fires right up but has a very rough idle like it's running on three cylinders.. After a few moments it clears up and runs just fine idles well and pulls strong..I suspected that the check valve might be the problem, put a new one in and it still does the same thing... So I'm thinking injector seals because if the system does hold pressure and there is a loss over time that would be the next weak point in the system... Any thoughts from you K Jet guys...

Thanks in advance

I did not catch the year of the car?

You might have a bad Lambda Sond relay. It turns on the frequency valve and connects the o-2 sensor to the computer that controls things.
It will run crappy if it has no frequency valve working.

The relay can get corroded inside and sticks open. It causes a lot of excess cranking and after starts runs crappy and suddenly run fine. That's after the relay closes.

It's located on the driver fender well. It's about one inch square and is next to the dipper relay that bigger?

Might be worth checking out especially the connector or inside the relay if it does click.. Also, listen for the frequency valve when ever you crank it. It should buzz.
That's located under but in front of the brake booster.

All of this information is comes from a my 1978 car. It's the only K-Jet I have.

Phil

Machine Man the year of the car is 1985 the last year of the B21FT

Wow, I did not know that they kept that engine around that long! I was thinking like 1982 or 83 especially with the K jet system.

Good thing I do not claim to be a Guru! (:-)
Phil

Make sure pin 7 on the Lambda computer is grounded when the engine is cold. That's the temp sensor input that grounds below a certain temp. It will run lousy until it worms up some if that is not grounded.

without ANY testing, it sounds like you need injectors-because they are leaking into the cylinder when off, and an accumulator because it cranks longer before starting when hot than cold. it MAY also need a control pressure regulator but that requires a pressure test. good luck, chuck.

Thanks guys.. But here's the rub like I said when after setting for hours and staring the car does fire right up no extra cranking needed and when hot there is no problem at all... As for the accumulator it's relatively new and so are the injectors....

Thanks in advance

Ah yes--sloppy reading. I'd still condemn at least one injector causing the rough running on hot startup. New or not there could be a leakdown problem. If you meant by "injector seals" - the internal injector sealing system - that's what I'm talking about. But if you mean the external seals ("O" rings) between the injector and the plastic housing and between the plastic housing and the cylinder head -- then no -- those seals would cause a lean misfire all the time and do not involve holding pressure. -- Dave

Thanks Dave but hot start up is fine cold is the problem...I'm also leaning toward a lazy injector also I think it's time for a pressure check...

Thanks

Hi,

It would be best to just replace the FI with one from a later model car. Like an 87 240. LH 2.2 is WAY better then kjet.


Goatman

Wrong injector system K Jet is the Bosch mechanical system that was used in many cars from Mercedes to Porsche to Volkswagen and of course Volvo until 1985 on there 240 B21FT turbos..... Thanks for all input guys...

..would include:

Audi
Bentley
BMW
De Lorean
Ferrari
M-B
Peugeot
Porsche
Rolls Royce
Saab


--
Bruce Young, '93 940-NA (current), 240s (one V8), 140s, 122s, since '63.

Yes you are correct Bosch engineers originally design this system for the aircraft industry but then refined it for the automotive folks.. Bullet proof system when the car is driven and maintained....

I'd say injectors too--as Porkface suggested. I'd think the extra cranking needed and rough running when hot would have more to do with the cylinders being soaked by the leaking injectors than any other possible problem. -- Dave