I have a '01 4wd Blazer. I got a 4.3 from a '05 truck. It appears the only things needed changing are the exhaust manifolds and the oil pan (sump tube). The truck engine does not have emission control. The old engine does. What has to be done to avoid flashing a code? I plan on removing the smog air pump. Will the ecm with truck engine need to be installed on the Blazer? The 05 engine does not have an EGR valve port on the intake. I did not want to monkey with 05 intake since all the other connections appear to be the same.
thanks

 

You will likely have to drill & tap a hole in the back of the block for the knock sensor.

You also will want to swap the lower intake manifold to get the EGR valve back or your PCM will not be happy.

 

thanks for that pointer.
Do you think i can just dead man the EGR valve with plug attached without it being in the intake? The old intake looks rough, i want to use the 05 one.

I will change the intake from old engine to new one. There is an injection difference from '01 to '05. I will scrap all the '05 stuff. So mr EGR gets to be installed like it should. thanks

 

You can use the injection spider from the '05 on your '01 intake. The '05 will have the MFI spider which is a common problem solving upgrade for the older SCFI spider.

On the EGR system, as I said already, your PCM will not be happy without a functioning EGR system.

 

Luck is with me, the knock sensor is on the '05 block already.
Has anyone removed the smog pump and ran with success?

 

On the knock sensor, is it the same as your '01? There was a change sometime between '01 & '02.

The AIR pump system falls under the same category as the EGR valve. To keep the PCM happy, you need to have it on there. With both, if you find someone with the proper PCM programming equipment, they can disable the codes for those systems, but you have to be careful with the EGR system. If the system isn't compensated for the lack of EGR flow, you can have problems later on down the road.

 

the knock sensor is on the back of the block in top left of center. correct? It may have a different plug for wiring, but it does have a port and one installed.

thanks for all the info. I will keep you informed on progress.

 

The early design was a thread in knock sensor. The later design was a bolt on. They are not compatible, as in you cannot simply change the plug on your wiring harness and have it work. If your current engine has the thread in type, you must drill/tap for that sensor.

 

ok, i will check that closer today. It looked threaded on the 05 block. more stress

 

the old style injection has two lines in. this is on a 2001 Blazer.
The newer style from an 05 4.3 truck engine only has one line in.
What is suggested to do with the return line since i will use the 05 new style?