200 10V stumbles, poor mileage

[Konstantine Bogach]

Just measured duty cycle - it is back to normal.  Before it was, at 
first, too slow and having wide sweep, as I only now realized after 
seeing current picture,  and then got pegged to max (~70%).   Engine 
works steady like rock.

Konstantine


On 01/02/2010 08:02 PM, Konstantine Bogach wrote:
> Stumbling is solved.  It was TPS (infamous soldering inside the 
> switch).   I had two such switches before but I could not recall this 
> symptom.  I did not check the signal on O2 sensor and did not drive 
> enough to see the mileage.  By the way, yesterday O2 sensor was pegged 
> to 0.1-0.2 V.  But when I tried to adjust the mixture to the rich end, 
> nothing changed until engine started to shake.
>  Car drives just super.  It is getting new shoes this week.
> As far as CSV goes,  I measured voltage on the connector when engine 
> was on.  I did not check wiring for hacking  yet.  I disconnected it a 
> few days ago.  That did not change anything  but I keep it 
> disconnected until I check the wiring.
>
> Thank you very much to everyone for help.   I would not be able to 
> keep this car without your help.
>
> Konstantine.
>
> On 01/02/2010 11:51 PM, Ben Swann wrote:
>>
>> Steve, Konstantine,
>>
>> The Cold Start valve only pulses in order to get the engine started, 
>> and therefore is only activated during cranking and possibly initial 
>> startup.  The CSV only pulses about 10 times when engine is stone 
>> cold.  Any more and the engine would flood quickly.
>>
>> The CSV does not activate during WOT and not only is not the type of 
>> injector that would be used for additional  fueling, but is in a bad 
>> location for adding fuel for performance - too much fuel would end up 
>> at cyl. #4 & 5 and #1 & 2 would be too lean.  So don't consider this 
>> location for supplementary injector, which should be placed before 
>> the throttle body or directly in muli-port configuration.
>>
>> If faulty CSV operation is suspected (I'm scepticatal) then get 
>> engine started and disconnect the connector to it.  Unless it 
>> actually is leaking, then CSV would be out of the picture for 
>> diagnosis.  I bet there is no difference and problem lies elsewhere.  
>> If CSV leaking is suspected, then unbolt it from the manifold and run 
>> fuel pump.  You would see it dripping fuel.
>>
>> Unless there is visual evidence of a hack job, or melted wiring 
>> inside the harness, I'd be looking for the problem elsewhere.
>>
>> The sypmtoms as described are that of massive air leak that opens up 
>> under load.
>>
>> Also, bad temp sendor or O2 sensor would cause problems as described 
>> as well as other culprits.
>>
>> Once again,  there should not be a path to ground at the CSV 
>> connector during normal engine operation.  If engine is not running, 
>> but ignition is on, I surmise that the loop would be closed and 
>> perhaps that is why it is suspect.  Check while engine is running - 
>> should be no continuity to ground.
>>
>> Ben
>>
>>
>