Longtooth,
The venturi seems to work fine it opens and closes freely.
Without physically observing the function of the CSV, it works. That is, there is no leakage from the bolt hole on the side of the valve once the bolt is removed and a test light lights up upon cranking the engine. I do plan on removing the CSV and observing the flow of fuel first hand.
I'll try to answer all the other questions:
Q 1. How long the engine can idle without throttle applied (beyond perhaps the initial startup throttle applied --- though I don't use any throttle on starting up).
A The engine will not idle at all without applied throttle. I have to keep throttle applied just enough to keep it running, too much or too little and it will stall.
Q 2. Does it initially idle without fits? and if so, how long after initial good idlel before it starts hiccuping or simply coughs and dies?
A It never has good idle. After 15 secs and a little more throttle, the idle will smooth out a bit but the car will put out a profuse amount of white/gray smoke and then backfire a few times.
Q 3. How far and for how long had you been driving since it's most recent immediately preceeding start-up when the engine died the last time you drove it?... and was it cold outside or just a balmy DC 55 degr F?
A The last time I drove the car, I was using it as a daily driver for 3 months. About 20 miles per day with some a few miles being highway. It was probably around 65 degrees F.
Q 4. How long had you driven the car (& how many times) before that last drive?
A As above. I have owned the car for 11 years. It has gone back and forth from being used one or twice a month to being a daily driver for a few months to a year at a time.
Q 5. Had you ever noticed any starting problems before... mild or not so mild ones?
A The car always started well except for when it needed new points or a point adjustment. It has had one major overhaul. I hate to admit this, but while in medical school and worried less about my car than my studies, I was not keeping track of engine coolant level. This car at the time did not have a functioning temp gauge. Well, one evening, I was driving on the highway when suddenly, poof. A mist of coolant in my face and the car stopped running. I pulled over, popped the hood and there you have it. The car over heated, and warped the head.
That was in 2001. The car got the head replaced with a rebuilt one and had been running fine ever since.
Q 6. How long (how often had you driven) after the previous mechanic's (or self) "tune-up" had occurred?
A Last tune up had been performed by a mechanic about 8 months prior to when car was last running. I don't believe much beyond points.
Dimitri
quote:
Originally posted by Longtooth
Dimitri,
Assuming something got stuck or broke, rather than a fuel delivery to the injector pump problem, have you checked the venturi? If it's stuck or the spring broke then....?
In general diagnosing a problem to it's source is either very, very simple, or not (duh). In your case I think it's long since past the simple type diagnosis.
When a problem doesn't lend itself to a simple diagnosis of it's source,the only option is to use a rigorous approach. You've already gone thru the ignition issues (plugs, points, condenser, coil, wires from distributor to plugs), so that leaves fuel / air.
On the fuel side, the rigorous obvious question is whether fuel's getting to each of the intake ports continuously for sufficient duration to maintain an idle and then increase with throttle applied. Less rigorously, and st the question is whether fuel's coming out of the injector pump ports on schedule. Basically, these questions apply to whether the pump's operating properly....
On the pump questions, at least one of the auxillary funcitons related to the "pump" is at the CSV... I already posed the question as to whether the Cold Start Valve is working as it should, since this controls the fuel (leaning it out from an initially rich mixture as water temperature increases).
For air, it boils down to the air intake filter or the venturi I think. I'd personally have difficulty believing that the air intake filter is problematic, but the rigourous approach to diagnosis starts there for air. If not that, then the venturi.
One thing which might help in diagnosis is more detail related to starting and idling:
1. How long the engine can idle without throttle applied (beyond perhaps the initial startup throttle applied --- though I don't use any throttle on starting up).
2. Does it initially idle without fits? and if so, how long after initial good idlel before it starts hiccuping or simply coughs and dies?
3. How far and for how long had you been driving since it's most recent immediately preceeding start-up when the engine died the last time you drove it?... and was it cold outside or just a balmy DC 55 degr F?
4. How long had you driven the car (& how many times) before that last drive?
5. Had you ever noticed any starting problems before... mild or not so mild ones?
6. How long (how often had you driven) after the previous mechanic's (or self) "tune-up" had occurred?
Longtooth
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'02 SL500 Sport
