Po301 and ticking noise

Asked by barby13 Nov 04, 2018 at 07:45 AM about the 2007 Chevrolet Cobalt LT Coupe FWD

Question type: Maintenance & Repair

07 cobalt 2.2  suddenly died, was driving fine up to
that point. Battery was replaced along with
alternator a few months before. Changed plugs
finally started with horrible chain slap noise. Only
code was po301 and po171. Replaced timing chain
and components.  Replaced crankshaft tensioner,  
crankshaft chain looked fine. Note: timing chain
was slightly loose but not broken. Then had no
start no crank, found starter was gone replaced ed
starter, starts fine. Makes slight ticking noise, now
code po301 back again and really low on power.
Doing a compression check today but any other
ideas?

3 Answers

157,345

Compression test will likely tell you #1 cylinder is down on compression. This may mean that one of the valves is bent. Just a guess though.

2 people found this helpful.

I did compression test, cyl 1 is 120, the rest is all 150. I continued to hear for tapping ticking noise and I definitely hear it under valve cover. Took it for a drive, no cel on, drove fine except for a little noise. This morning its rough and shaky. Could this be sticking valve, bent valve? Would replacing head cure problem?

157,345

If possible have a qualified mechanic evaluate it. It could even be a camshaft / valve lash issue. Pretty hard to figure out sitting behind this monitor.

1 people found this helpful.

Your Answer:

Cobalt

Looking for a Used Cobalt in your area?

CarGurus has 13 nationwide Cobalt listings starting at $3,500.

Postal Code:

CarGurus Experts

  • #1
    munron
    Reputation
    8,130
  • #2
    John Carson
    Reputation
    2,270
  • #3
    MoGo
    Reputation
    1,980
View All

Find great deals from top-rated dealers

Search

Related Models For Sale

Used Chevrolet Impala
9 Great Deals out of 130 listings starting at $4,888
Used Toyota Corolla
150 Great Deals out of 2,284 listings starting at $2,699
Used Ford Mustang
51 Great Deals out of 1,662 listings starting at $5,977
Used Honda Civic
175 Great Deals out of 4,082 listings starting at $440
Used Chevrolet Malibu
48 Great Deals out of 1,071 listings starting at $2,495
Used Honda Accord
52 Great Deals out of 997 listings starting at $2,995
Used Chevrolet Corvette
24 Great Deals out of 667 listings starting at $10,989
Used Chevrolet Colorado
37 Great Deals out of 1,211 listings starting at $4,995
Used Chevrolet Silverado 1500
201 Great Deals out of 8,235 listings starting at $6,995
Used Chevrolet HHR
13 listings starting at $3,999
Used Lexus IS
19 Great Deals out of 414 listings starting at $4,400
Used Chevrolet Equinox
96 Great Deals out of 3,375 listings starting at $1,695
Used Ford Explorer
71 Great Deals out of 2,016 listings starting at $3,333

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use. Content will be removed if CarGurus becomes aware that it violates our policies.