Buick and Oldsmobile Overheating, GMC P0410 - Live Chat With A Mechanic

Question: Yes..I have a 2000 Buick century thats been over heasting..changed thermostat and water pump. Even used gasket repair. Now it appears to be a leak when I opened the radiator to drain some antifreeze before I used the gasket repair. The heat comes in and out while i'm driving. Very little pressure in the hoses.
 Mechanic: one moment... In order for my car to get the heat to continue to keep the car cool I have to press harder on the accelerator. What engine size?

3.1L SFI.
 Lower intake manifold gaskets very common problem, also rear cylinder head gasket.

What would be a solution because i've tried gasket repair. A day ago and it seems to still be trying to over heat.
 Sealer almost never works on this engine, pressure test the system to find the leak, remove plugs to look for signs of burning coolant internally.

Okay...thanks.

 

Question: Hi. i just did a upper gasket rebuild on my 99 olds alero 3.4. i had a blown headgasket now when i start my car, it acts as if i dont have the spark plug wires set up correctly. The set up is idiot proof, and all spark system worked perfectly before i did the work to it.
 Mechanic: Does it run?

No and if i can get it to start, its a bad stutter as if bad missfire or out of time and the timing was fine before i blew the headgasket, and i know that that will not mess up the timing.
 Did you put put the pushrods in the correct order?

I believe so, i had them set aside but i also had a helper, are they different lengths?
 Yes. The intake and exhaust are different lenghts.

Thank you off hand, do you know what ones are longer so i can double check?
 See this link for 3100 or 3400 pushrod locations.

Thank you soo much, you just saved me a weeks worth of work at least :)


Question: Hello. I have a P0410 code and don't know what else to do?
 Mechanic: What year and make? What has been done to it?
2004 gmc envoy. I have replaced bank 1 O2 sensor and both air pumps.
 OK. There is a common problem with these. Give me a moment to get you a link to the article... The secondary air diverter valve is common to fail. Here is a description and picture of A.I.R. Diverter Valve.
Ok. So I should change that?
 Most likely, but if there is water in the line, the pump may also have locked up. Testing with a scanner to control the motor and valve would be needed to confirm either or both.
Thank you so much for your help !