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Hi Victor,
I have done a injector bypass leak test and they seem to be equal as my video will show, there is no missing while the engine is running and the engine runs smoothly, i have tried to reach the area were knock sensor is located but with no luck, there is no codes logged also and the noise is only there on idle a few times then disappears the exact same cyclic noise on Nanone video, i will also look up a manual on the Antara you have to see if the engine is the same as mine, could come in handy, i will get the fuel trims checked, also the DPF is on the engine exhaust ports and the Catalytic converter is below that, the Pre Cat O2 is below the DPF were would the Post Cat O2 be located Victor,, thanks Victor,, Lurchy

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Lurchy, doesn’t visually appear to be a lot wrong with your leak off results (although the total quantities weren’t calibrated measurements) so I guess you don’t have any serious problems with worn / sticking injector needless.

On our vehicles the CAT is before the DPF, not after it - as a matter of fact the CAT is incorporated into the same casing as the DPF. The ones with a CAT after the DPF are the SCR CATs to tackle NOx emissions, our systems don’t have any post-DPF NOx treatment. Personally I’ve never even had cause to remove the heat shield from my DPF so couldn’t tell you exactly what’s in there but the locations of the pre- and post-cat temp sensor shown on the thread that gcmarcal posted a while back when he changed his DPF.
DIY DPF replacement
 

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Lurchy, doesn’t visually appear to be a lot wrong with your leak off results (although the total quantities weren’t calibrated measurements) so I guess you don’t have any serious problems with worn / sticking injector needless.

On our vehicles the CAT is before the DPF, not after it - as a matter of fact the CAT is incorporated into the same casing as the DPF. The ones with a CAT after the DPF are the SCR CATs to tackle NOx emissions, our systems don’t have any post-DPF NOx treatment. Personally I’ve never even had cause to remove the heat shield from my DPF so couldn’t tell you exactly what’s in there but the locations of the pre- and post-cat temp sensor shown on the thread that gcmarcal posted a while back when he changed his DPF.
DIY DPF replacement
Hi Victor,
Just an update mate on the Idle Ticking Issue
I have not had the infamous rhythmic ticking sound again after i changed the 2 Vacuum solenoids on the rear of my motor that control Swirl Flaps and Turbo Boost,
I remember Yourself or Ed mentioned the ticking could be caused by the Fuel Trims,, i think this may have been the problem as the trims would possibly be out of calibration due to the Swirl Flaps and Boost issue due to the solenoids which caused my P200A-00 DTC before i changed the solenoids,
My car is going great, No Codes and also it does a lot more kilometers before needing to do a DPF Regen.
Please give me your thoughts on my post, i had also said i was going to change the knock sensor / terminals but after replacing the solenoids i did not do it as the ticking noise stopped,
I am some what in the dark how exactly the fuel trims work but have read on other internet posts that the ECU controls the amount of fuel, Air and Exhaust resirc and boost to keep the fuel trims correct in values to deal with amount of injector time and fuel flow depending on what the engine load is in real time.
Regards Lurchy :)
 
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Hi Lurchy me old mucker, good to hear from you. Glad you got things sorted out since you changed the solenoids, maybe a pointer there for other owners. You see it’s never been mentioned before and now that you’ve filled us in it seems to be the solenoids could have been at fault in other cases on here.

Re the fuel trims put me down as No2 in that I can’t give you a comprehensive answer, I think you’d need the ECU manual to give you all the ins and outs but you’re right in what you already said.

It’s not like the petrol engines which best operate at a 14.7 to 1 stoichiometric ratio so they have 2 oxygen sensors, pre- and post- CAT. The first one monitors the air/fuel ratio and feeds info back to the ECU which is constantly dithering, adjusting the fuel /air ratio. The post-CAT sensor feeds back its results of the fuel trim adjustments but it’s also monitoring the health of the CAT. When the frequency ratio of sensor 1 and 2 approaches a specified value the Three Way Catalyst (TWC) malfunction is diagnosed and a CEL light comes on.

Diesels don’t operate on the same principles, we have widely differing stoi ratios. Ours uses a Diesel Oxidising Catalyst with a lambda sensor pre-CAT and temp sensor in the DPF area. The lambda sensor is needed to monitor the air/fuel ratio during DPF regeneration when the stoi ratio can go down to less than 1:1. The CAT is responsible for raising the EGT to about 600 deg C to get the blow torch action going and start burning particulate matter that’s accumulated in the DPF. The temp sensor is vital to make sure the DPF doesn’t go into meltdown and is used by the ECU in fuel and turbo boost calculations.

There’s a whole lot of other things going on of course but you’d need a team of technical writers and a load of manuals to describe it all fully. Main thing is that yoiours is going all right now so lets hope for continued success.
 

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@Lurchy or @Victor: Can someone post the OEM numbers for the solenoids? It would be helpful to find them when they will be needed :)
 

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@Lurchy or @Victor: Can someone post the OEM numbers for the solenoids? It would be helpful to find them when they will be needed :)

Ches, Due to topic fragmentation (more than one topic on same/similar thing) I think you will find your question is answered in the following link post #34 DTC P200A and loss of power. EGR issue?
I think this is the solenoid under discussion.
 
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