Hey guys, new to the forum, kinda new to volvos. I just bought my second Volvo, a mint condition 1979 242 4 speed. I had a 84 240DL wagon turbo brick in high school, but that was a while ago. I will post pics of the car, as soon as i find my cable, but I have a question. Today i drove a 30 mile trip to my moms house, and turn the car off, came back 5 mins later, and BOOM, it runs like ****. Im talking bad idle (sounded cool as **** though, like its got a crazy cam or somthing) and had no power (haha like a stock B21 has power to begin wth lol) and it got worse from there on. It started to sound like it was a diesel, and then even less power. i couldnt go any faster than 40 while flooring it, and it was misfiring, and popping. ALL BAD. i checked the oil and coolant, looks good, no oil coolant mixing. no signs of a bad head gasket. I pulled the plugs and they were white like it is leaning out bad ( looked like they were covered in cocaine) so i changed them with NGK V power copper plugs. I need to get new plug wires tomorrow since the plug wires dont fit theese plugs. So theres the low down. Has anyone ever had an issue like this? I going to check all the vacum lines tomorrow. I check the timing marks and every thing is lined up (i have already changed the cam seal, and the engine mounts) I als have a new oil leak from right above the water pump. i am a toyota guy, and i dont know much about the B21. I do have to say I love this car though, and cant wait to drive it again. Thanks in advance guys, i hope I was through enough with the information behind my question!

 

Have you a fuel pressure gauge? It might be a bad main fuel pump(everybody seems to think a fuel pump ether dies or works and there is no in between but I have seen some dying pumps/malfunctioning pumps that have done some freaky s**t)

A dying pump will produce inconsistent pressure

How is your cat convertor? if it is partially blocked then that causes issues

 

I do not have a fuel pressure gauge at hand, but i can get one from my tool box at my fashas house. Whats a good pressure reading that i should look for? Also I have not looked at my exhaust system too much, I have only looked at from the rear wheels back, since my muffle fell off. I was thinking fuel pump as well, and i replaced the fuel pump fuses ( god theese fuses and fuse panels suck) and a weak pump makes a lot of sense. I dont have any whining from it though, and I have a brand new fuel filter. I heard theese cars have a fuel dist. block? My mom used to mess around with mini mopars (shelby chargers, omnis, daytonas, lancers, and other turbo chyslers) and said the ignition system is a hall effect? She said she will look at it if i cant figure it out, since i dont know what hall effect is. Any ****ing who, I will check out the fuel system after i get my wires and get it started tomorrow. Also i havent cold started it since the problem. I dunno if i need to for a better diagnosis? Thank you Journey force!

 

you need a volvo specific adapter for a fuel pressure gauge, they hook inline to the fuel line where it goes into the injection .... you have K-Jetronics injection on that 1979 242,that needs like 60 or 65PSI, I believe. later LH injection systems used 42-46psi above manifold vacuum.

I highly recommend replacing ALL the $#@$@# ceramic fuses with new ones that are copper or brass. you can get these online in a kit as 'mercedes w124 fuses', you want the german ones, not the american Buss or Littlefuse, those are tin or aluminum and suck. the kit for a w124 (thats a late 80s/early 90s 300D/300E/etc) is more than enough fuses to replace all of them on a 240.

also, clean the fuse holder contacts with a clean soft pink pencil eraser, this will take off the corrosion without removing the gold plating.

K-Jetronics has a 'fuel distributor' which modulates the fuel to the injectors by measuring the airflow via a venturi plate. if dirty fuel got into this fuel distributor, they are a pain to clean out, very delicate, many little parts inside.

this is the k-jet fuel distributor and air flow sensor from a Mercedes 300E 6 cylinder. the volvo one is very similar but under the intake manifold so kinda hard to see, and has 4 instead of 6 fuel lines.

 

check out k-jet.org as I have the same car...only difference is that it has 10 years of animal hair IN EVERY NOOK AND CRANNY....owner lives in a ranch so I am guessing goat? or lab.

As far as fuel in these models I have had many issues. CIS system..so check out k-jet.org
You got the following:
Fuel warm up regulator...behind dist cap (returns fuel back to tank) Bosch..$290 with core return in Texas (you may try a BMW 80's model or SAAB and yank it out...just check part number)
Fuel distributor (under intake manifold) Bosch $Bosch still makes it at $800 euros!!!!!! or junk yard
intank pump: $38 easy stuff.
outside pump: $139 or junk yard...got me one today for 10 dollars...nice.
Accumulator: $179 and completely forgot what it does

Distributor/Warm up Regulator/Accumulator ALL HAVE SPRINGS INSIDE AND HAVE LEARNED THEY GO BAD!!!!!! I HAVE READ YOU CAN RE-DO THE WARM UP BUT IT SOUNDS LIKE A DELICATE PROCESS.

Marvel Mystery Oil is fantastic in K-jet systems...4 oz to a tank...since it is all mechanical and injectors are always spraying...lube is good.

My outside pump whizzed sporadically AND IT WAS A DINOSAUR...so changed it. you will need a fuel filter to fuel pump hose from an 84 and later model Volvo to connect from Fuel pump to accumulator...as the old pump has different connections.

 

Test out your resistor by the coil as mine was gone and was causing problems....you can find some on line for 20 bucks or less...

 

HAVE DONE THE FOLLOWING ON MY 79 242...

RATED FROM 1-10 Where 10 is most difficult.

Trans Mount: 4 easy
Motor Mounts: 6 medium...ps..I dont have power steering so had tons of room on starter side
InTank pump: 5 if you drop the ping pong don't panic...use salad tongues and fish out...voala
outside pump: 6 note...remove the fuel lines 8mm bolts/clips 3 toward engine and two to tank so you can hang the entire fuel pump housing/whatever as the fittings are pain to undo as you need to back them up
Manual gear box fluid: 3 ATF 1 quart...two plugs on driver side of trans...easy but use a transfer pump or i just screwed a spray bottle to the quart of ATF and streamed it to the top nut.
Diff gear oil: 3
Fuel Relay: 1 under your steering column.
JUST ASK....I'VE DONE A BIT OF SERVICE ALREADY AND HAVE LEARNED THE HARD WAY.

 

Wow, thanks guys! I appreciate all the replies! Today i found out it will be 5 days before my plug wires come in. but i pulled out all of the injectors and guess what? #2 no spray. the rest, spray weird, like a squirt bottle. so hopefully i just need to clean everything out.

 

see if you have a diesel injection service company around you. they can properly clean and test those k-jet injectors... you need to pump cleaner through them at like 60PSI as they have a pressure actuated valve inside.

 

I will try that. I have an Dr. injector not to far from me, i wonder if they can do it? I'm really hoping to put it back together and it work, this is my daily driver till June when i get my FRS.

 

actually, you might swap the bad injector with another, and see if its the injector, or the port of the fuel distributor thats gummed up.

 

Im going to have to go to the junkyard for that. I only have extra supra injectors lol. but i will try that to see if i can isolate the problem

 

well, I meant swap two injectors on your car... if the one thats dribbling still dribbles when its hooked up to a different fuel line, then the problem is the injector. if the other 'good' injector is dribbling when you hook it up in the position that was bad, then its the fuel distributor port thats clogged.

those K-Jet fuel distributors are pretty complicated inside, they should be disassembled only under very clean conditions, there's a pile of springs, slide valves, diaphragms, etc inside, everything needs to be totally clean and free of dust etc when reassembled.

 

A year or two ago I tried to find a place that would clean my k-jet injectors. They all pretty much just laughed at me. So I devised a way to clean them myself: I removed the injectors from the car, set my air compressor to supply air at the opening pressure for the injectors (forgot what it is, but easy to look up), then filled the injector as full as possible with injector cleaner, followed by attaching it to the compressor hose and letting it spray the cleaner out. I just kept repeating it until I got a good spray pattern (cone-shaped). One injector never did better than half a cone. The spray pattern improved with repetition on all four injectors, but I don't know if it improved the way the engine ran, because I replaced the injector seals at the same time (which were crumbling).

 

I've heard you can put them in an ultrasonic cleaner and that can do wonders.

and yes, plan on getting new injector seals, as air leaks at the injectors will negatively impact engine running

 

QUESTION FOR YOU:

when you engage a gear...do you hear a clunk?

I changed my u joints and improved the clunk a bit...
The driveshaft has a play....were I can turn it about a quarter turn....is that normal for a stick shift?
I crawled under an 80 242 wagon and tried turning the driveshaft and of course the wheel turned but there was no freaking play.....you turn the driveshaft and the wheel turns...but you turn my driveshaft and you have to turn it a quarter turn before it engages the differential....?

clutch is worn already
ran the car for a month with no clutch fork return spring(bought it like that) and now there is no play in the clutch pedal as before it would sink 4inches...now it is nice and springy.

 

if a manual transmission clunks when you shift it smoothly into gear with the clutch fully depressed, chances are the synchros are worn. how about when you're moving, and shift from, say, 2nd to 3rd ? that also should be quite smooth if you take your time shifting and don't force it quickly into gear.

a 1/4 turn of play sounds a little excessive, but I suppose it depends on what gear its in when you test it. if this is a 4 speed with separate external electric overdrive as opposed to a 5-speed, that could add some play.

oh. a malfunctioning overdrive could be causing clunks when shifting too, like if the OD is randomly switching on/off. on a M46 type transmission with the separate OD, the OD is supposed to only be allowed when you're already in 4th gear, there is a switch on the side of the transmission that tells the OD relay this, and when you shift out of 4th, it should turn the OD relay off automatically. Its not inconceivable that this system has been cobbled by a previous owner.

[caveat: I've never owned a Volvo with a stick shift, my OD experience is from our old British TR-6 that used the same J type overdrive, and my general stick shift experience is mostly from VW Rabbits and Jettas that I drove in the 80s/90s].

 

it clunks on 1st to 4th...1st being the loudest and the clunk noice is hardly noticeable in 4th...but there...

Synchros? I take it it has to do with the differential?

 

no, synchros are inside the transmission. there's a set of them for each gear.

when you step on the clutch, the transmission input shaft is floating, the output shaft is always connected to the main drive shaft to the differential and the rear wheels. so now you move the shifter from neutral into a gear, and the shift forks first engage the 'synchros' which are like little clutches on the gear shaft that spin the input shaft so it matches the speed of the gear you're shifting into, then locks that gear to the input shaft. now you can release the clutch, which connects the engine to the input shaft and drives the car.

manual transmission shift smoothest when you shift them smoothly, don't jerk them into gear, but also don't try and shift them too slowly. and they shift smoothest if you can match the input shaft speed to the gear you're going into at your current road speed. when you are upshifting (from a lower gear to a higher one), you put the clutch in while the engine is at a high RPM, and shift it into neutral, and the input shaft starts slowing down on its own... if you time your shift into the higher gear right, you're shifting it just as the input shaft is going the speed it will be at your road speed in this new gear, it will snick into place really smoothly, and unclutch and resume accelerating.

downshifting, if you clutch in, shift to neutral, clutch out and blip the throttle lightly to spin up the input shaft to the new higher revs, clutch in and shift, and time all that right, it will shift into the new lower gear when everything is already turning the same RPM, and be smoother. this is called double clutching. the art is in not overdoing it.

 

I see...I image searched the synchros and one guy on turbobricks had broken synchros so he took a few pics.....well thanks...fortunately my transmission is tiny and would take it apart...but where the heck do you buy synchros?

I double clutch on my car as it is smooth and hardly a clunk noice...but if you try to single clutch it...forget it...Jay Leno said the same thing when driving a Jaguar...4speed no od...double clutch for sure. thanks again.