Exhaust and fuelling?
 

Hello all,

I recently bought a 1999 S40 T4 for pennies from a family member. And I am currently going through bringing it back to its former glory.

I have a couple of questions regarding fitments of some parts;

1) The exhaust has snapped between the first silencer and the joint to the cat converter section. I was wondering if the middle section of the exhaust is the same as other S40s? I.e the 1.8 or 2.0 litre models, as there are a few at our local scrap yard with great condition exhausts, or would they be too smaller diameter? Failing that the only one I can find for reasonable money is made by Clarius, which are terrible for rot!

2) I was warned that the fuel pump had been replaced by one from a smaller engined S40, I am not sure which engine but I assume it won't be able to keep up with the demand of the T4 under high boost? The car seems to cut for a second or so when held at WOT in 3rd/4th as the revs build up, could this be pump related? Seems worse when under 1/4 of a tank and happens when low on fuel and cornering!

Can anyone recommend a decent aftermarket replacement for the standard T4 pump, as they seem very expensive new at around £270!

Any input would be great!

Thanks,

Mike.

The T4 pump is more powerful than on the other petrol engines. According to Haynes it delivers 150l/h, while the rest manage 120l/h. So if you ask me it is completely plausible that the lower pump power causes power problems at WOT. Especially if you feel it more when low on fuel and cornering.

Thank you for that info ww1dm1! Could you recommend a decent aftermarket fuel pump which may fit? As the official ones seem a little expensive at £270! I am not planning on driving the car again until I have these issues sorted anyway due to fears of it running lean. I am going to just bite the bullet and order the klarius exhaust I think!

Regards,

Mike.

Never changed mine so can't recommend anything specific, though for that price I've seen whole sender units together with the floater which you probably don't need.

Best option is to retrofit a Walbro 342 into the original sender unit. Make sure you get a genuine one, lots of copies and fakes floating around eBay!

Guide here:
http://www.30forty50.com/forum/topic..._fromsearch__1

The Walbro 342 is recommended over the 340 in the guide as the pickup is more similar to the OEM pump so will give zero issues with pickup uphill or round corners.

you can buy A full Swedish replacement unit
a lot cheaper than original volvo but I've never used
the company so dont know the quality http://partsforvolvosonline.com

Hello all,

Just to let you know, replacement spark plugs have cured the stuttering under boost, it now pulls well in all gears, but the old spark plugs indicated that it was running lean, so I need to order a new fuel pump too I think!

Thanks,

Mike.

Worth changing the fuel filter to remove some restriction from the system if it's getting on a bit, I'd swear mine pulls better after changing the old one over!

I second that. Filter is an issue with these cars, i swear my humble GDi was better after doing it.

Thanks for the tip guys, I will get one ordered, judging by the state of the spark plugs I am guessing it hasn't received much maintenance in a few years. But I do know it has a non turbo s40 fuel pump fitted which I imagine won't be helping matters.

The symptoms I had before changing the spark plugs was spluttering under boost, the exact same feeling/sound as when the traction control kicks in (which I guess would be spark cut rather than fuel cut as it reacts pretty quick!)

That has now gone, the issue now is. even with around 3/4 of a tank of premium unleaded, when you put your foot down (say in 2nd or 3rd), the car feels like it surges slightly. It's hard to explain, it pulls really well all the time, but feels like there are little surges every now and again where it pulls harder? Only in short bursts or if you roll on to the throttle gently!

I am going to pull the new plugs and check the colour of them, my guess is that they will also be lean.

Coils looked to be in good condition, as did the plug leads.

Thanks for your help so far guys! I have never experienced a car having running issues from worn spark plugs! But then again I haven't had many turbo petrols either!

Thanks,

Mike.