2012 Tahoe won't start

[Billeickmann]

My Tahoe has 55,000 miles and has been very reliable. Last week, I got the check engine light, but it continued to run properly on my way home. Just a few miles. Next start, it ran very rough and stalled. Check engine light was still on. I tried cleaning the MAF, as it had never been done and put in a new air filter. Now, she cranks just fine, but does not even kick. No hint of firing. I pulled a spark plug boot and it sparked a plug when cranked. Not a big spark, but it jumped the gap. I then tried some starting fluid and nothing. Three tries and just a little cough. Could it be a weak spark?

I next bought a code reader off Amazon. It shows the vehicle VIN, but no codes. I tried cranking with the code reader on and still no code. The check engine light is still on. Repeated several times.

I bought the truck new Jan. 2013 and it has had no engine work, so maybe I am overdue. Any suggestions please?

 

[Doubeleive]

My Tahoe has 55,000 miles and has been very reliable. Last week, I got the check engine light, but it continued to run properly on my way home. Just a few miles. Next start, it ran very rough and stalled. Check engine light was still on. I tried cleaning the MAF, as it had never been done and put in a new air filter. Now, she cranks just fine, but does not even kick. No hint of firing. I pulled a spark plug boot and it sparked a plug when cranked. Not a big spark, but it jumped the gap. I then tried some starting fluid and nothing. Three tries and just a little cough. Could it be a weak spark?

I next bought a code reader off Amazon. It shows the vehicle VIN, but no codes. I tried cranking with the code reader on and still no code. The check engine light is still on. Repeated several times.

I bought the truck new Jan. 2013 and it has had no engine work, so maybe I am overdue. Any suggestions please?

check to be sure you have fuel pressure

 

[wsteele]

My Tahoe has 55,000 miles and has been very reliable. Last week, I got the check engine light, but it continued to run properly on my way home. Just a few miles. Next start, it ran very rough and stalled. Check engine light was still on. I tried cleaning the MAF, as it had never been done and put in a new air filter. Now, she cranks just fine, but does not even kick. No hint of firing. I pulled a spark plug boot and it sparked a plug when cranked. Not a big spark, but it jumped the gap. I then tried some starting fluid and nothing. Three tries and just a little cough. Could it be a weak spark?

I next bought a code reader off Amazon. It shows the vehicle VIN, but no codes. I tried cranking with the code reader on and still no code. The check engine light is still on. Repeated several times.

I bought the truck new Jan. 2013 and it has had no engine work, so maybe I am overdue. Any suggestions please?

If you have a CEL and your scanner isn't displaying a code, I would maybe consider a problem with the code scanner first.

 

[OR VietVet]

Code scanner or operator problem. What color was the "weak" spark you saw? Orange or blue? Need fuel pressure reading. Age of tune related components? Original? At 55k miles I would assume they are.

 

[swathdiver]

My Tahoe has 55,000 miles and has been very reliable. Last week, I got the check engine light, but it continued to run properly on my way home. Just a few miles. Next start, it ran very rough and stalled. Check engine light was still on. I tried cleaning the MAF, as it had never been done and put in a new air filter. Now, she cranks just fine, but does not even kick. No hint of firing. I pulled a spark plug boot and it sparked a plug when cranked. Not a big spark, but it jumped the gap. I then tried some starting fluid and nothing. Three tries and just a little cough. Could it be a weak spark?

I next bought a code reader off Amazon. It shows the vehicle VIN, but no codes. I tried cranking with the code reader on and still no code. The check engine light is still on. Repeated several times.

I bought the truck new Jan. 2013 and it has had no engine work, so maybe I am overdue. Any suggestions please?

Bill, you have to get those codes, otherwise you're just guessing and wasting time and maybe money. Seems like a fuel problem to me but I haven't seen the codes!

 

[Billeickmann]

OK. I went out to my truck to try the code reader again and she started. There was no check engine light, but she did run rough. It slowly became normal after a minute. I tried the code reader and I got P0172, system too rich bank 1 and P0175 system too rich bank 2.

 

[Billeickmann]

Shut her off and let her cool. Started again and got the same two codes again. Yes, all of the engine is original. I have only done tires, brakes, oil, battery, and filters.

 

[wsteele]

OK. I went out to my truck to try the code reader again and she started. There was no check engine light, but she did run rough. It slowly became normal after a minute. I tried the code reader and I got P0172, system too rich bank 1 and P0175 system too rich bank 2.

Is your truck a flex fuel version?

 

[wsteele]

Also, if you could determine if your scan tool can do live data display, that is probably going to be helpful down the road (most do).

 

[Billeickmann]

Yes my truck has the 5.3 flex fuel engine and the code reader does do live data.