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numerous problems

volvo4life1

New member
Joined
Jun 13, 2010
Location
vancouver,BC
240 with b21ft. if I don't warm it up it will sputter, but when its at operating temp it will drive fine. also when i am sitting at light it will idle a 1500. For example if i turn it off and then go in the store and come back like 10 min later it will idle back at 1000. I'm not sure it I turn it off and then on again it will do the same but It most likely will,. could vacuum leaks do this? this all started happening after doing m46 swap.
edit: im also getting bad gas milage . 14mpg. im usually getting 17/18mpg
 
Someone tell you that you were going to get better fuel economy with the M-46? :rofl:

Start with checking for vacuum leaks.... Chances are that you knocked something loose or split a vacuum line while shaking things up doing the transectomy.

Check injector seals..... Common failure.
 
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My '76 does the same thing. I call it the anti-choke, since it will hardly idle when cold and will idle somewhere between 1100 to 1500 when warm.
 
is a cold start injecter in my car or something long those lines. Im thinking maby its not getting enough fuel when she is not at operating temp.
 
Yes it has a cold start injector..... But as it's name implies... It is used only during a cold start; IE while the starter is being operated.

Running lean? Checked for vacuum leaks yet?
 
Could thermo time switch be a possibility? I don't actually know much about them, but my mom's '76 does the same thing and she was told that she needed a new one. Could be unrelated though...there are a lot of things that can cause those problems. As everyone has said, vacuum leaks are especially problematic with kjet. It's not a bad idea to renew the hoses if it's never been done. They inevitably crack and split.
 
Could thermo time switch be a possibility? I don't actually know much about them, but my mom's '76 does the same thing and she was told that she needed a new one. Could be unrelated though...there are a lot of things that can cause those problems. As everyone has said, vacuum leaks are especially problematic with kjet. It's not a bad idea to renew the hoses if it's never been done. They inevitably crack and split.

Jen the thermo-Time switch decides if the cold start injector gets fired and if it does, for how long. Thermo+Time. All while the engine is cranking.

Fuel mixture while it warms up is done by the control pressure regulator... AKA 'Warm-up regulator' that changes control pressure to add more fuel when cold.

More often then not K-Jet drivability issues are due to vacuum leaks.
 
im going to be replace all the vaccum hose this weekend so we will she what she does

*BUT FIRST*......get a section of fuel hose and SWEEP THE ENGINE BAY FOR
a *HISSING NOISE*....checking for vac leaks FIRST before you start throwing parts
at it.... :omg:
have your GREENBOOK HANDY!
see also:
http://www.volvowiringdiagrams.com/?dir=volvo/K-Jetronic
there is a WEALTH OF *VERY GOOD FACTORY* info there
enough that you *should be able* to suss your trubbles forthwith....

notice a TREND HERE?? VAC leaks / VAC leaks / VAC leaks!! :nod:
 
I couldn't find any vacuum leaks. Im not sure how everything works exactly but it seems like to me that something is getting stuck open. cause It will ilde at 1000 when i first start it, then when i drive it and sit at a red light it will idle at 1500. but if i turn it off the on it will idle back at 1500. any ideas guys. its starting to piss me off
 
oh cause i check on ipd to see which one fits and it says they are all interchangeable. Ill see if I can get a k-jet one then

again please:
YEAR of your car
MODEL of your car
any MODS you have done (swopped out bits / added stuff / thrown stuff away....)

*ALL OF THE ABOVE MATTER*

and finally WHAT YEAR 740 IAC motor did you swop in??
go to : http://www.volvowiringdiagrams.com/?dir=volvo/K-Jetronic
if your car is indeed a KJet iteration
or:
http://www.volvowiringdiagrams.com/?dir=volvo/LH 1.0
http://www.volvowiringdiagrams.com/?dir=volvo/LH 2.0
http://www.volvowiringdiagrams.com/?dir=volvo/LH 2.2
http://www.volvowiringdiagrams.com/?dir=volvo/LH 2.4
as appropriate....
you have READ THIS STUFF and actually DO the testing as indicated in
these GREENBOOK and other *TEXTS*...we can help if you get
confused in testing but there is NO SUBSTITUTE for your active
testing and participation GUIDED BY THE FACTORY INFORMATION
the fact that you've "Swopped out a trans" means you ARE capable of'
doing the work..it just needs DIRECTION and the books are your BASICS! :nod:
 
1983 242 turbo mods are turbo back exhaust,12psi and larger intercooler. half the time the adobe links don't load so that is why im here. There is some vaccum hoses that are plug off,but they have been like that ever since I got the car so they really don't affect anything.

edit: not sure what year it was to be to honest.
 
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