mr_blackstock
G'day,
Over the past couple of weeks while driving she has been loosing power while driving around 100kmh, gradually loosing more and more. Not missing or back firing, as though running super lean or running out of fuel. The other day she got so bad, i was struggling to top 40kmh, finally I tried to super richen the mixture to try and help, just made it worse. I could not get the revs above idle, the idle was fine however. I tried opening up the throttle to full, she would just hiccup and a little back fire, like she was missing on three pots.
I have not had a chance to collect her from the side of the road yet, but when I do I will be checking everything, from fuel pump to fuel filter blockage, to dizzy, et all.
I do not think it is the recent K-jet transplant I did, but i guess i will be checking the pressure regulator at least.
This seems to have been a very gradual issue, at the start she would have trouble getting to the top of mild hills, then she would have trouble accelerating faster than 100kmh, then she would sort of starve when I put her in over drive instead of increase revs.
Anyway, i was wondering if others had come across this, and perhaps offer some thoughts while I arrange to get her towed. The local tow operators wanted $250 to tow her 20kms!
cheers, Gareth
Nosi
hi,
we had what sounds like the exact same problem with the 242gt. it was particularly like that when hot. although we ultimately changed a lot of things, the problem you describe most likely related to the coil or the distributer. I suggest you start with the coil. hope that helps !
mr_blockstock
Thanks for that, I have a few spare coils and dizzies, I will give them a try.
Cheers, Gareth
Philia_Bear
Where are you based?
mr_blockstock
I am based a little south of Ararat, Victoria.
Gareth
mr_blockstock
Alright...
I got the car running, tested the coil=fine, took the pipe off the fuel filter and cranked the car=fine, checked spark at all plugs=fine, re-checked timing=fine, checked k-jet sensor plate=not binding, fine, injectors buzzing?=fine, injectors squirting?=fine, re-checked vacuum hoses?=fine, blocked air intake?=fine,
I managed to get the car starting and idling well. I try to rev the engine, and she falters around 2500rpm, after a bit she gets up to 3500rpm but burps and farts getting there. When she is warm she cannot get past 2500rpm.
Questions: do the fuel pumps pump faster as the revs increase, in other words, if the fuel coming out via the fuel filter is coming out like a garden hose, and could fill a coke bottle in less than a minute, would this be enough to think both fuel pumps were fine?
I think the dizzy advance unit is fine, as when I reconnect the vacuum hose after timing the ignition, I can see the mark on the flywheel advance all the way.
My next step will be checking the CPR and in tank pump. just in case they are faulty when the revs get higher. Any ideas out there?
cheers, Gareth
Nosi
hi, I would suggest replacing the coil. the problem I had was that it was intermittent. It would work when cold, then become variable, then fail totally when hot. my number is 0412 seven four eight 309 if you want to chat.
mr_blockstock
Hello,
I replaced the coil with a spare one and the problem persisted. Would a bad coil prevent the engine from revving past 2500rpm?
cheers, Gareth
Nosi
I believe so. assuming your new coil is ok, and the leads are all good, then that would rule out the coil and leads. the hall sensor in the distributer is the next likely issue.
the fuel pump flows at one rate when 12v is connected. so if you have fuel coming out, then the main pump and in tank pumps are not the problem. its easy to test by pulling one injector ( it should just slip out) and then placing it into a modified clear plastic bottle, then turning over the motor and seeing the injector spray. be careful of course.
I chased a similar issue or ages on the 242, and it was either coil or dizzy related. on my 940's the similar issues were coil and coil leads.
mr_blockstock
G'day,
I will use a meter to test both my coils tonight, and I will check the resistance in the leads too. I have three spare dizzies, but they are all different types to mine (I will be selling them on gumtree when i get a chance)
I will look in my manual tonight to research how I can test a hall sensor. I pulled one injector the other day and it had a good spray.
Thanks for the help,
gareth
mr_blackstock
G'day,
Some updates... I tested the leads, all within 4.5ohms, I tested the coils I had, all three and they all had no resistance on the primary winding, and all three were higher or lesser in resistance than what the manual required. The ballast resistor also had no resistance. So. I have ordered a new coil, bought a new ballast resistor. The manual was no help in instructing about how to test a TS-2 dizzy and ECU for good connections. I hope the new coil works, as the next step is replacing the CPR unit.
I also replaced the in-tank pump with another one with a two year old pump, still the problem persisted. At least now I know I have a good spare.
Gareth
irishbastard
Sounds like the distributor, I've got a 740 GL that did the same thing, and I can't be bothered getting it fixed so it's just sitting here taking up more car space
mr_blockstock
Hello,
I was trying to diagnose the dizzy, but the manual offers bugger all instruction on the how to. If the coil fails to make a difference I might put a wanted ad on the board for a decent TS-2 dizzy. With your 740, how did you know for sure it was the dizzy?
cheers, Gareth
egads (she/her)
jamesinc
Regarding fuel pressure, yes it is constant at all times. Excess fuel is returned back to the tank via the return hose.
mr_blockstock
G'day,
The link to bosch dizzies will be helpful, I will read it through more tonight, the only trouble is in the section detailing testing the ECU and pickup, it describes different coloured wires to mine. Either way it will make good reading, cheers.
Gareth
volvodriverman
Fuel pressure at idle might be misleading, I've just replaced the fuel tank in my 76 245 b21e kjet car as it ate another fuel pump. On inspection the tank was rusted to shit & full of flaky rusty mud... It showed perfect pressure at idle but flow was drastically impaired & the car grew increasingly slower until the pump failed.
egads (she/her)
Yeah, ECU stuff is only generally similar unfortunately. Volvo specific testing guide is proving hard to track down so might need someone with real world skills to help as I am just an informed knowledge regurgitator.
mr_blackstock
G'day,
Just an update, got the new NGK leads, and new Bosch coil, no difference. The car runs and revs better, idles pretty sweet too! But the moment I try to rev the engine, she hangs around 2000 rpm, missing etc, then gets up to normal revs.
I am going to replace the CPR next with the old one, see if that helps. Either that or try and find a replacement dizzy as the manual is no help with my current one.
Any more ideas?
Cheers, Gareth
volvo1975
maybe replace your rev sensor !! on top of bell housing with a bolt and then connects with a clip
