94 960

960it · Post by **960it** » 14 Dec 2009, 20:14

Hello, I just purchased a 94 960 with alittle over 200k on it, the person I bought it from said that both fuel pumps were bad so I replaced the in tank pump. when I turned the ignition key on the other pump was working as well so I have yet to replace that pump. My main concern now Is a misfire on the rear cyl. I replaced the rear coil pack as well as the spark plug that was in there. After I checked for spark I checked for power and Ground using a test light on both the injector and the coil pack, but that rear cyl still has a miss , Im some what stumped as where to go next, should I check fuel pressure or Is there something else to look for thanks Guys

DanR · Post by **DanR** » 15 Dec 2009, 08:35

I am thinking you have a vacuum leak, possibly in a hose or a fitting, but most likely it is the intake gasket. I have heard of using propane gas or starting fluid while the engine is running. Spray either around the intake gasket at the faulty cylinder, should the idle smooth out, then a leak is the culprit.

DanR '94 964 346,000 miles (112,000 on the new engine)

Post by **billofdurham** » 15 Dec 2009, 11:38

960it, welcome to Matthew's Volvo Site.

I agree with DanR about a possible intake leak. You can also use carb cleaner.

Bill.

960it · Post by **960it** » 15 Dec 2009, 19:40

Thanks guys Ill give that a try tonight.and thanks for the quick response

960it · Post by **960it** » 15 Dec 2009, 20:10

well I sprayed the rear cylinder area with carb/throttle body cleaner and nothing changed I also sprayed the rest of the intake manifold as well as the vacuum lines around the intake manifold.

960it · Post by **960it** » 15 Dec 2009, 20:30

Do you guys think that I might have a bad injector or a dirty fuel rail causing the injector to not fire the right amount of fuel to fire the cyl

960it · Post by **960it** » 16 Dec 2009, 16:58

Anybody have any other suggestions

bright · Post by **bright** » 17 Dec 2009, 01:46

960it wrote:well I sprayed the rear cylinder area with carb/throttle body cleaner and nothing changed I also sprayed the rest of the intake manifold as well as the vacuum lines around the intake manifold.

First, welcome to the site.

Second, I am sorry to hear that you too purchased a 960. Be glad that it wasn't a 1995.

(Love the car, great design, atrocious mpg, don't love the "idiosyncrasies" of my model and year.)

I've used this trick, and it does work but its not as obvious as you'd think. Use engine starter BUT also have a fire extinguisher and for the love of your eyes wear protective glasses/goggle.

You might hear your engine burble up a little, but that's going to be it. Check to see if any of the hoses are cracked. Also, be sure to put your head close to the engine (not in it) and listen for hissing. That's a ringer for a external vacuum leak. Other than that, I wish I could help more. Billofdurham knows his stuff.

Post by **billofdurham** » 17 Dec 2009, 12:04

A bad injector would set a code. Have you checked for fault codes?

You can check the injector with an ohmmeter/multimeter. Disconnect the connector and check the resistance which should be 16 ohms at 68F (20C). This is a very basic test but to go deeper you need specialist equipment.

Bill.

960it · Post by **960it** » 17 Dec 2009, 19:06

Well last night I pulled the fuel rail out to swap injectors. I pulled the rear inj. first then pulled the next one up from the rear, when I did that it dumped a bunch of fuel out , so I swapped injectors in hopes that the miss would move frm the rear cyl to the next one up. But the miss is still on the rear cyl, so that means that the inj isnt bad. Is their a possibility that the fuel rail could be stopped up and not causing the fuel to get to the inj?