|
|
|
|
| Author |
|
|
Registered
Join Date: Nov 2008
Posts: 6
|
Need some help with my engine!!!
New here and am getting desperate for help on my damned 1977 924 Martini and Rossi edition. Basically my issue is the right fuel to air ratio to get the car idling and accelerating just fine.
So far all I'm getting is a rough/ok idle but no acceleration past 1000rpms... but if I start the car and quickly get on the gas it will climb 2000+rpms. If I let off the gas and let it drop below 2000rpms, and step on the gas to try to gain more rpms the engine dies a little bit and quickly gets to that damn 1000rpm hump. Eventually it will hit the idle around 1000rpms and wont go any higher unless I restart and do my trick all over again. The guy before me rigged a cold start valve switch onto the carb. I can quickly turn it on and accelerate past 1000rpms but it wont idle with the switch on, and I'm sure its not meant for all the time use. I've tried a little tinkering here and there, but in reality I have no damn clue what I'm doing. Some guy told me about the air flow sensor plate, but I don't know whether to adjust it up or down. I think there are other things that I can adjust but I'm not sure what and how much and where they are. All help will be greatly appreciated, even a good luck post  .
Last edited by MikeyJ; 11-24-2008 at 08:04 PM.. |
||
11-24-2008, 01:06 PM
|
|
|
Registered
Join Date: Nov 2008
Posts: 6
|
Messed around with the fuel distributor spring loaded piston thing. Sometimes the car idling at 3000rpms! Other times it wouldn't even start with the number one fuel injector in place. Its leading me to believe that my fuel distributor is bad...
|
||
|
11-24-2008, 08:03 PM
|
|
|
Redline Racer
Join Date: Jan 2007
Posts: 2,444
|
You might want to give http://924.org/contents.htm a look. There's a few people here that know the 924 that might be able to answer that, but most only know 924S/944.
__________________
1987 silver 924S made it to 225k mi! Sent to the big garage in the sky |
||
|
11-24-2008, 08:23 PM
|
|
|
Redline Racer
Join Date: Jan 2007
Posts: 2,444
|
...oh yeah, and good luck with that!
__________________
1987 silver 924S made it to 225k mi! Sent to the big garage in the sky |
||
|
11-24-2008, 08:26 PM
|
|
|
Registered
|
CIS can be a pain to get right; you really need to start with a new filter and pressure tests (plural). Definitely check out www.924board.org, good people and allot of info on 924s of all years.
__________________
Rick 93 968 (My summer car), 05 Cayenne S (My winter car), 79 924 (Wife's summer car), 02 C230k (Wife's winter car), |
||
|
11-25-2008, 04:31 AM
|
|
|
Registered
Join Date: Feb 2001
Location: Buzzards Bay, Ma, USA
Posts: 620
|
You have mechanical fuel injection, a lot of very precisely machined parts working together to keep the proper fuel to the engine. Very primitive by today's standards but it works reasonably well and trouble free when it works. Did the car sit for a while? Is there a chance anything in the fuel dist. got gummed up?
Haynes describes in good detail a fuel flow test where you remove the injectors and place each one in it's own container and measure flow over time. I believe you can run this test for different throttle positions. It might give you some useful information. If you don't have Haynes get one, they do a very good job with the 924, much better than with the 944. Poke around on line, there is a lot of information on the CIS available, much of which can be downloaded. Learn all you can before you start taking anything apart. This thing is like a fine swiss watch and that fuel distrubitor will be hard to replace and probably cost more than you paid for the whole car........ Did you check all the vacuum lines? Good luck, Jon
__________________
87 924S 82 924-Gone. 80 924 parts car-Gone. |
||
|
11-25-2008, 05:06 AM
|
|
|
|
Back from Beyond
Join Date: Nov 2004
Location: Alberta, Canada
Posts: 2,697
|
I agree about going to www.924board.org too. CIS seems to require very methodical approaches to fix. There are plenty of variables and your only hope of fixing the car is to rule them out one by one and work slowly and meticulously. You'll need a CIS pressure tester to give you an accurate story, too. Plus a very long 3mm allen tool for adjusting the mixture.
I'd check fuel flow rate at injectors, system pressure and cold start components first. You've got fire, else it wouldn't run at all. Go on a take-no-prisoners hunt for false air. This is a big issue. There's more. Unlike the Haynes for 944, the Haynes for the 924 is a great manual and takes you through CIS fault-finding well. That said, when it's tweaked up properly it's reliable and simple.
__________________
'88 944 Auto - project, kinda '87 944 Auto - died saving my wife '84 944 5SP - crushed under shop roof during snow storm All others GONE! |
||
|
11-25-2008, 10:41 AM
|
|
|
Registered
Join Date: Nov 2008
Posts: 6
|
Yes I have the 924 Haynes manual... reading it religiously :P. Only problem is I'm short on cash for buying more testing equipment, possibly only to find another bad part to replace.
|
||
|
11-25-2008, 10:47 AM
|
|
|
Registered
Join Date: Feb 2001
Location: Buzzards Bay, Ma, USA
Posts: 620
|
My experience was that adjusting the idle mixture didn't do much. It's just to reduce emissions at idle and didn't really affect performance.
Don't give up. These engines are very reliable once you get everything sorted out. Jon
__________________
87 924S 82 924-Gone. 80 924 parts car-Gone. |
||
|
11-25-2008, 11:04 AM
|
|
