84 Euro 308 QV - throttle on engine start

Hi everyone,

I'm the new owner of an 1984 308 QV in the UK. Previous owners have been on here so I've already got some of the history from previous posts!

On of my niggles is that the car requires a bit of throttle to start, both warm and cold, This is a bit of an issue on my sloping driveway with a handbrake that barely works!

Is it normal for these cars to require some throttle on engine start? The manual says not (at least for cold starts) and my previous K-Jet cars never did, but I thought I'd check with you guys first.

If not, any suggestions on what to check, in what order? I think the previous owner disconnected the cold start plug so I'm guessing that's a sign of something being slightly off.

Thanks

 

My 85 QV Euro has the cold start disconnected. I asked the workshop who said they do this on all 308 GTBQV. Cold start I just use about 1/3 throttle and it fires right up. Hot start takes a bit more cranking and I probably give it more throttle. But it always starts!

Handbrake is fine just after adjusting but gets progressively worse as the rear pads wear. Naff after about 2k miles

 

No, it's abnormal on the K-Jet without Lambda models like yours to need any throttle pedal motion to cold start and cold-run -- you are just masking another problem. My first suspects would be:

WUR cold-control pressure too high
and/or mixture set very lean
and maybe a little AAV not opening as much as it should when cold.
(and your cold start injector system + TTS needs to be looked at if it is unplugged).

 

My car is interesting and extremely consistent: starts with 2-3 second crank and a little throttle when cold. Starts again almost immediately with no need to hit the gas when hot. And takes a long crank, often two, to start when warm (e.g. stopped for 30 minutes somewhere). Always like that in cold and warm weather. A very consistent behavior. Mechanic also disconnected the cold start valve when we did major service, so doesn’t the bit of throttle essentially accomplish the same thing (bring up slightly higher idle rev)?

 

That can be a symptom of the residual fuel pressure falling too quickly at warm engine shutoff (it should stay up at 2.5~3 bar for 20 minutes minimum).

If you mean the cold start air valve on a US version, its purpose is to provide a (very) high cold RPM after start-up to heat up the catalytic converter more quickly. It is not intended as something needed for cold start-up. Many do disable it, or modify it to make the cold high idle RPM not so crazy high.

 

Interesting! I just started it “the way the man said”! Mixture (hot gas test for MOT (annual test) is good. I must try no throttle!

 

Just adding another data point: have never had to touch the throttle pedal to start my '83 US QV regardless the situation: Cold start, warm start, or fully heat-soaked hot start. That being said, it does take a few cranks to fire when fully heat-soaked.
- Dave

 

The QV owners manual states' Open throttle slightly for hot starts'

 

I believe that recommendation only appears in the euro 308i-2V OM and euro 308QV OM, but not in any of the other injected 308 OMs. Also, that recommendation is for a "very hot" engine -- the post I was responding too said "Starts again almost immediately with no need to hit the gas when hot. And takes a long crank, often two, to start when warm (e.g. stopped for 30 minutes somewhere)". A warm (not very hot) injected 308 should start well without needing to use the accelerator pedal.

 

I'm glad we agree.

 

Not my OM...maybe a reco for the Lambda-equipped Kjet?
From Page 32 in the OM for my '83 US QV (260/83):
Cold Engine Starting: "....Do not step on accelerator pedal until engine is running smoothly."
Hot Engine Starting: "Hot engine starting is identical to the procedure for cold starts."
- Dave

 

I must have been to 20 different Bosch CIS related schools. Bosch was always quite adamant that no throttle be used to start the car. The way CIS works it will lean the mixture possibly causing a backfire. When a CIS car backfires it can displace the airflow plate backwards pushing its locating pin back and resulting in an incorrectly positioned plate. Needing throttle or improving anything by disconnecting the cold start valve are indicative of some other operational problem in the injection system. Both our TR and our 328 are started routinely hot or cold by me reaching in through the window and twisting the key.

 

My owners manual for the 1988 Mondial 3.2 CH88 says no throttle when cold, very small throttle when hot, I presume to take the throttle position sensor just off its at rest setting if your car is equipped with that TPS. This is with the later KE3 Bosch system. But I have found it starts just as well when hot with no throttle as well.