chevy47390

hello from France,

I have two Trans Sport ( Venture ) at home built in 1999 and 2001.
These are great cars !
Last week , while I was driving peacefully on a country road , I felt a loss of power in a very important side .
I was then on LGP and I went on petrol, the engine seemed a little better and I returned to the house is 70 km away.
The idle is quite regular and less good on LPG monopint . but goes well in turns off in park
I measured the cuts between 10 and 11 ( kg/cm2 ) very good, and gap the sparks at 0.060 (1.52 mm)
and I changed the Manifold Absolute Pressure : same defect and no alarm check the dashboard . ( i have a DTC OBDII reader )

These power shortages are accompagned with vibrations in the transmission, as the holes on the road , so I fear that the loss of power is due to the torque converter or gearbox.
On drive position D the speeds grow good and it cruise good at 60 miles /hour when it get this speed.

Thank you for your help and feedback to those who are familiar with these cars.
What tests to check torque converter and box gear ?

sincerely

chevy47390

hello,

The tranmission oil level was at the average level in the middle of the mini maxi area. Oil was clean, pink, with about 20,000 miles.

I just added a quart of DEXRON III for to be up to the max.
the shocks in the transmission are gone, the "CHECK" lamp does flash no more at the request of effort.
the raises are back to normal with the good power

So it seems that the PCM limits the engine when the power does not pass
How?

sincerely.

groovygran

My 2002 venture van shows a oil can light (like a genie lamp) and also a sign like a thermometer on waves. The van loses power and yesterday finally quit. The garage did a diognostic test, replaced the serpentine belt and a new battery. Today it was doing the same thing...Why

chevy47390

can you explain :
"My 2002 venture van shows a oil can light (like a genie lamp) and also a sign like a thermometer on waves. The van loses power and yesterday finally quit."

I do not quite understand what you write. Rephrase as simply as possible .

when you have a loss of power without DTC , generally , it is a ignition problem that is revealed by a flashing lamp "check engine" .
indeed gaps ignition causes incomplete combustion detected by two " O2 Sensor" . but these " misfire " do not appear when driving on LPG, and appear when asked an effort at low speeds (on gasoline).

Someone wrote somewhere :
"a loose gas cap WILL NOT issue a flashing check engine light , only a severe misfire Will issue a check engine light to flash - . JM [ June 23, 2010] "

My Venture is now OK (correct all)
With these cars, you need a OBD 2 code reader and learn to use it. I just noticed it was a measure in real time " O2sensors " O2B1S1 and O2B1S2 . great!

on my Venture I changed the coil block and the plate below and since the magic is back with a vehicle that was so quiet here everyone is admiring engine

Thank you and congratulations , the guys at GM

jlutty3

replace plugs and wires?

chevy47390

replace plugs and wires?

I guess this question is for me.

I first replaced the spark plugs without success, and in a second time I replaced all the spark plug wires . always without success. (Replacement MAP and IAC . I have a lot of material in advance! ) So I replaced back the elements considered good .

to remove these misfires , it only remained that the coils and the connecting plate ( if we exclude the PCM ) . and that was the problem.
But I did not recognize what was defective element , one or more coils or the connecting plate (which may be electronic contains )
The difficulty is that the sparks were well supplied and that measures ohmmeter give nothing : Coils vary between 5100 and 5400 ohms. the spark plug wires are between 1100 and 1600 ohms for the original wires ( 60.000miles ) and between 3000 and 3200 ohms for new ones AC label .
I do not know if the plug tester to be connected between the spark plug and ignition wire , would have helped locate the fault. this tester is very difficult to implement on the bank 2 cylinder 1 3 5 .

How to test ignition Venture could be another topic
whether the deficiencies found in operation can be easily reproduced and tested....
The commonly accepted solution is to replace everything without thinking.

chevy47390

Accuracy for readers
what I called "connecting plate" is the ICM "Ignition Control Module".
it has three connectors and the three coils are connected above.

Generally, the above described defect is due to the coils.