My 1993 945 is making a lot of noise when under power. I had the pipe coming from the exhaust manifold changed and the rear muffler replaced. It still sounds like there is an exhaust leak. How can you tell if the exhaust manifold gasket is leaking? How hard are they to replace? I think it may be the problem.
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2010 XC90R, 2002 XC70 Ocean Race, 1993 945.

I have taken a leaf blower ducted taped to the tail pipe and then soap spray the manifold to see any bubbles. You will most likely see bubbles from the downpipe gasket to turbo outlet. Tighten the 3 nuts/bolts.

If it turns out to be a gasket, you do not need to remove the turbo to replace them.

It will take a little time, but you can back out the studs (run 2 nuts up against each other on the stud then loosen the stud by turning the inside nut CCW). There will be sufficient play to allow you to slip out the old & slip in the new gaskets. Then, using the same nut technique, you can replace the studs and then tighten the manifold.

This method negates the need to remove the down-pipe & turbo, you never need to get under the car.

Note: this will not allow you to do a thorough inspection of the manifold which, as a previous poster noted, may be cracked.


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1999 E320 1994 F150 1989 560 SL 1986 560 SL (deceased) 1988 300 TE (departed) 1994 945T (daughter's) 1988 244DL (fallow) 1986 242Ti (fallow) 1968 GT500KR (under restoration)

Most likely not your gaskets (there are 4, one for each cylinder), as the proud owner of four '93s over the years I can tell you that I have even reused them several times over and they still never leaked; they are quite good quality gaskets. Also, the turbo/engine pipe joint is quite robust as well.

If you have ruled out the turbo/engine pipe junction, that pretty much narrows it down.

I would guess that you have a cracked exhaust manifold. DO NOT spray ANYTHING on the manifold when the car is running. I mean no offense to the other poster, under normal circumstances this is a sound technique but the 91-94 turbos switched from the copper lock-plated through bolts to hold the turbo on to studs taped into the manifold. These new manifold castings were problematic and brittle, and were extremely prone to cracking under thermal stress. If it isn't cracked now it certainly will be after that.

I would further guess that if you remove the manifold and turn it over there will be one or more large cracks vertically directly behind where the turbo hooks up. YOu might be able to check it with a mechanics mirror and a shoplight without taking it off the car.

I never pass a manifold at the boneyard without checking it, that's how common this is. Nobody sees it much as it is rare to have the manifold out of the car altogether. I honestly have never seen one without cracks; it is only sometimes that they crack through and leak.

I will try to post pictures later, as I am in the middle of a head gasket change and everything is off the car.

I hope I am wrong, and it is your gaskets.

good luck

RStarkie is correct. I did this job on my 940 Turbo. The turbo plumbing makes it a bigger job, but not impossible by any means. The one thing I messed up was the o-ring on the turbo oil return line when I put everything back together. Had a massive oil leak. Be extra careful when you reassemble everything that the o-ring isn't getting manhandled. It's only a less-than-$1 part, but took about an hour to fix my mistake.

Hope the fix goes smoothly!
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Guid ('92 745 257k, '91 940 SE 278k,)

First try torquing your bolts. If that doesn't produce a loose bolt that tightening would cure then try this. With the motor STONE COLD, wet the areas suspected with a spritz bottle filled with degreaser or a little water and dish soap. Start the motor and keep it wet as it heats. A leak will produce bubbles. Just don't try this on a hot surface or you can warp or crack the metal.

A short section of hose can be a big help. One end at your ear and the other moving around the area you think might be leaking. As you approach the leaking area the noise will become more apparent at your ear.

If it is a NA engine the task is not bad, but a turbo increases the difficulty factor. The added work of changing out the turbo exhaust manifold gasket calls for the highest quality gasket set which are the ones purchased from Volvo. A bit pricey but you don't want to use a poor quality aftermarket set that might not last very long and then you would be facing the task again.

Even if you decide not to do the job yourself I would start spraying the exhaust manifold nuts with Kroil or PB Blaster now. Reapply on a regular basis to give you an advantage at removing the nuts without breaking a stud off. That adds a whole other twist to the job.

Randy