polcan

Hey
I had the same problem with my 88 S4.Turned out to be busted fuel pressure regulator.
You can check them with vacuum pump
Salute

Z928328

I have the same problem before- First start of the day- Its fine- If you switch it off & try to start it again- It cant start, & puff of smoke(Fuel smell) will come out from tail pipe. Only way to start it is too press the gas pedal. It appears to be the all 3 fuel regulator & diaphragm, The vacuum hose suck in fuel into the intake causes it hard to start.

Bill Ball

My trusty S4 continues to amaze me. I'm on the original regulator and dampers.

Watch it blow up tomorrow, now that I've said that.

Mongo

They always do. They always hear you talking about them.

joejoe

Not to hijack thread, but when reading values for temp 2 sensor what does it mean if all values are lower than norm? When cold (car has hard warm start also) reading is reading was 3.2k when fully hot reading was 140. This was found on both pins. Could this cause hard hot start?

johnu

thanks guys, lots of stuff to check and/or change....I will start with the cheapest stuff first and work my way up from there

Stromius

Off readings of the Temp 2 could cause rich mixture just like leaky fpr or dampers. Per your scenario, if accurate, would make the ECU think it's cold and run richer or too rich to start....my interpretation. YMMV

The Fixer

My 928 owner's manual states when the car motor is warm to depress the accelerator pedal to the floor when starting.

When my car is warm, this is how i start it, otherwise it may not start quickly as it normally does.

I embrace this old school stuff, part of owning a classic car.

Bill Ball

It does? Never, ever had to do that. Only with engines that are flooded by some fueling issues (leaky injectors, bad FPR/damper diaphragms).

StratfordShark

I bought set of Ford Motorsport injectors for my previous S4 from Summit Racing - cheapert han having old Bosch injectors cleaned! I don't know if they still stock them - it was several years back.

Anyway not quite plug and play but almost. You need to replace the lower o-rings with larger ones. I don't have note of dimensions but I think Roger Tyson sells them separately. At the time I bought 8 of the Porsche injector kits (contain washers, o-rings,pintle caps) but I only used the o-rings!

The Ford injectors have the correct groove at top for metal clip which secures injector to fuel rail.

The Fixer

Yes my MY 1983S manual says to press the accelerator to the floor when starting a warm motor, and not touch the pedal when cold.

My car has low miles and has been really maintained well.
The original owner changed the oil on average every 1500-2000 miles, found a couple of records where he changed it at 6XX miles and 12XX miles from previous change. The same exotic repair shop serviced it since 1987. So it makes great compression. Really pulls nice.

But..
When the motor is warm it takes a few tries to fire up w/o depressing the pedal, with the pedal depressed as per manual's instructions it fires up with authority. Love this car more every day.

I'm curious if the later cars have this written in their manuals.


My MY 1986 911 Carrera (w/ gen 1 Bosche Motronic) states in owner's manual: page 21 'Ignition' To start a hot engine depress the accelerator pedal to the floor.

johnu

Just read my 1987 manual...says NOT to press the pedal because the cars sensors will compensate and start it normally

Thanks for the info on the Ford injectors

Still haven't tried to tackle this problem....having too much fun driving it!!!!!

John

am

In a 1979 it says not to depress the Accelerator for warm or cold start (page 40)

am

By the way, I also have a starting problem when warm. I must floor the gas pedal for it to start when warm. Ok when cold and restart. That problem since a few days only. This post will be useful.

joejoe

Just replaced the temp2 sensor and car starts better when hot. Still a long crank, but it will start. Tomorrow I will check MAF and idle with kens' blinkr'. Hopefully this will help a bit also.