[thebrooks]

I just acquired this Volvo from the original owner. It has only 88,000 miles and appears it was meticuliosly maintained. However, last summer the previous owner let it sit for 6 months and when she attempted to start it, it bucked, stalled and would'nt maintain an idle. Since I bought it, I have drained the old gas (smelled kinda funky!), replaced the fuel filter, and replaced the main fuel pump. The fuel pressure was still weak/intermittant, so I had a local mechanic replace the in-tank fuel pump (i was not personally worthy of this task!).

The mechanic has confirmed it now has the req'd fuel pressure (from the fuel line @ fuel filter). However, now it seems the (excess?) fuel immediately fouls the plugs, causing the car to briefly start and then stall. The only thing he knew to check today is the air/fuel mixture at the air flow sensor (? i had to had to locate for him a specific 3mm allen wrench for this purpose). I've not heard from him today so, i'm assuming this did not correct the problem.

Because the mechanic has no experience with Volvo's, he said that beyond the repairs mentioned above, he would not know what steps to take next.
Since I live in a small town, without a Volvo shop or tech'n, I'm left with few
choices!!!

I've since been pounding the repair manuals that accompanied the car. Their are some areas/repairs that seem might address the problems, but there was no guidance as to HOW TO CHECK or TEST; only part replacement info.

Can anyone please offer simple 'test' procedures for the following parts, that I can convey to my mechanic; Fuel Distributor, Control Pressure Regulator and/or Air Flow Sensor (is the 'line pressure regulator' contained inside the 'fuel distributor'?).

Please feel free to suggest any other possible problems or area's that should be considered. Sorry for such grand inquiry, but I will be grateful for any & all help!

Thank you, Brooks

 

[DVolvoguy777]

Re: 1978 245 B21F C.I. *!*HELP*!* (thebrooks)

There is a Bosch manual that describes in detail how to troubleshoot this CI system in your Volvo. The last time that I looked at it ( 11 years ago ) It seemed there was a rubber baffle in the diaphragm of the fuel distributor that could be dry rotted. This manual can be had at any auto parts house I believe.

Either that one or more of the fuel injectors can be fouled. A simple injector service can be done to fix that.

There is an other thing that could cause this. There are two O rings on each fuel injector that goes into the head. Those O rings more than likely need replacing. That is very easy to do on your own. Just a 10 mill socket and the correct size O rings and petroleum jelly to lube them and re-install.

My 76 wagon had three of the injectors with cracked Orings. Same with the 80 GT.

 

[gdill2]

Re: 1978 245 B21F C.I. *!*HELP*!* (DVolvoguy777)

Nice Volvo wagon!

While you are checking the engine wiring harness for deterioration. corroded junctions and faulty grounds plus a look at ALL vacuum lines/junctions I'll go fetch some info sites on 240 troubleshooting.

George Dill

ps: Brooks - We would love to see your Volvo at the VCOA Meet in October in/at Lake Tahoe!

http://www.vcoa.org/events/200...ional/

 

[thebrooks]

Re: 1978 245 B21F C.I. *!*HELP*!* (DVolvoguy777)

Hello~~

Thank for the info!

I was wondering....if the fuel ijectors need cleaning/svc'g, would'nt this mean their clogged? Would 'clogged' injectors allow the excess fuel at the plugs, which is now the problem??

Puzzled

Brooks

 

[thebrooks]

Re: 1978 245 B21F C.I. *!*HELP*!* (gdill2)

Thanks for the info!

With your suggestions about junctions & grounds, are you suggesting that their may be underlying electrical problem? In my novice mind I thought that with the wet plugs it must be a fuel issue!?!

Any specific junctions or relays that would stimulate the C.I. to send excess fuel
(does this question even make sense?!?)?

How'z about the fuel pump relay? This was my assumption on the f.p. relay; if gas is proceeding to the plugs - the fuel pump relay is OK (?). Or, does it play a role in modifying/adjusting amount of fuel pressure/flow??

Thank you again, Brooks

 

[DVolvoguy777]

Also! Check the wire harness that goes inbetween the alternator and engine block. That could also be a culpret.

The fuel pump relay just turns the pumps on and off. If you have pressure, you have ingition.

The CI fuel injection is mostly mechanical. Your car does not have a MAF it just has an air mass sensor that goes in the intake after the air filter. There may be a temp sensor in the air box but I do not remember.

http://www.autofind.com.au/sit...8&p=2

Check that link for info on CI FI.

 

[username]

keep in mind that the very simple CIS and KCIS fuel system does require some special tools for proper diagnosis and even service....... that system is used in many european cars so you may do just as well finding a local vintage to even contemporary MB technician to diagnosis it..... if you don't have a volvo guy

the pressure guages are a bit pricey, for starters, but will save you lots of blindfolded dart throwing if you are having actual CIS troubles