Hi All,
I have exhausted every possible reason that I can think of for an intermittent starting problem on my S70.

On occasional starts, maybe every fourth or fifth time on average, the engine fires but cuts out immediately. Three, four, five or six further attempts to start and it fires up and runs fine. Occurs with both cold and hot starts.

so far i have...
Tried starting with out depressing accelerator.
Removed key from switch and reinserted.
Removed key from switch, activated central locking, unlocked and tried again. (I think it could be related to the security system)
Replaced fuel filter.
Cleaned out throttle body (twice).
Used both keys. I was told that sometimes keys lose their memory.
Fitted new genuine fuel relay.
Checked for spark from the coil on no starting and found good spark to be there.

There have never been any engine fault light displays. i'm told this means that computer diagnosis wont show any error codes. I next plan to try swapping coils with my other S70 but would apporeciate any ideas. Where are you Klaus?
Laurie Sydney

I am always waiting for you to post! Very interesting...
If you have a manual transmission, there is a switch on the clutch pedal that could be at fault...
If it is an automatic, try shifting it to N before starting again...

But, you are probably correct, there is an immobilizer switch that will not allow the car to run. That ring is on the backside of the key portion of the ignition switch and has been known to wear out. I have never been there and done that, sorry.

The 1998s have "normal" old fashion keys, no memory, so the key is not your problem. Sitting in the driver's seat and locking/unlocking the doors with the remote should help sometimes and that points to the immobilizer.

Klaus
EDIT: Don't rule out the electrical portion of the ignition switch. Check it by jiggling the key to see if the warning lights flicker in pos II.

--
The 164 has a new home, all I am left with are a 95 854T and a 98 V70R :)

Thnx Guys,
Klaus will immobilizer probs show up as error codes if I take the car to a volvo service outlet for a diagnostic test?
Laurie

I cannot say. The 1995 didn't have codes for the alarm system, perhaps the 1998 is better. If it is the immobilizer, then you need to get it fixed. It will only get worse.

Luck,
Klaus
--
The 164 has a new home, all I am left with are a 95 854T and a 98 V70R :)

Wasn't there a common problem of a heavy keychain wrecking the ignition switch?
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'97 855na, Mobil 1, K&N, various IPD's and eBay's

Hello L,

I heard about your starting problem. I had a similar problem with my 99.

It was fuel pump time!!!

The wire had broke off and made intermittent contact. Check the fuel pressure during the no start, Autozone sells a gauge that screws right on for ~$30 There is a schrader valve on the end of the fuel rail.

Good Luck!!
Goaster

Thnx Goaster,
Will check fuel pressure. What should it be?
I tried Klaus's suggestion of wriggling the key at the II position on the ign switch but could generate no display light changes. Sorry Klaus. I did check once when it wouldnt start and there was spark from the coil. This brings us back to fuel so I'll check the pump out.
Thnx All
Laurie