Service Engine Soon light intermittent No code

JimmyMac · Post by **JimmyMac** » Sat Aug 30, 2008 5:27 am

2003 S-10 crew cab 49000 miles on truck. "Service Engine Soon" light very intermitten comes during quick accelerating, driving higher speeds (50-70mph) with/without cruise control and with/without air conditioning on longer distances. No codes. Found some wear inside cap and rotor and replaced. No help though.

Ok Finally back been a long while, Misc. reasons. Anyway problem with intrmitten light was solved a while back. Gas Cap Seal - No problem since

04crewvt · Post by **04crewvt** » Sat Aug 30, 2008 1:52 pm

Get it to the dealership ASAP and have them check out the engine for wear, that is what started my painful odyssey code 0335 --blown engine I chased my tail around until I had replaced all the obvious possible culprits and ended up seizing a bearing and having to have an entire new motor installed. It started with the same symptoms about 20k before it would set a code and by then the damage was done.

JimmyMac · Post by **JimmyMac** » Sat Aug 30, 2008 4:41 pm

That SUCKS!!!!!! I reallv hope this is not my problem. If it turns out to be the same I will NEVER talk good about the reliability of a Chevy. Namely the S-10. This is something I noticed and been trying to figure out for a long time. Low mileage and I do take care of my truck. Of course Chevy or anybody else can not troublshoot when its an intermitten problem. "Can not troubleshoot if it aint broke" BUT should this be my problem, I find it hard to beleive we are the ONLY two to ever have this happen. Got to be something Chevy can/should do......... and that is regardless 2003, mileage or whatever.
Thanks 04crewvt

04crewvt · Post by **04crewvt** » Sat Aug 30, 2008 4:54 pm

We are not there is another out there who blazed the path if you look through the thread you will see a bunch of threads from Justin's problems. Luckily for him they occurred in warranty and he got a new motor from the deal. Scary thing is the 2003 and 2004 years were built by people who knew there plant was closing and they were probably using every part they had on hand to build the last vehicles off the line. Who knows what quality control was being implemented.

Post by **HenryJ** » Sat Aug 30, 2008 4:58 pm

JimmyMac wrote:I reallv hope this is not my problem.

I am guessing that you HAVE changed the oil more than three times in the last five years. You are probably OK.

Keep in mind that the light is there to tell you that you are polluting the atmosphere. It is not really a gloom and doom light. It will go off when the problem corrects itself.
If it flickers, I would suspect a ground problem somewhere. That does not sound like normal operation. If you have no other symptoms, this it very likely.

Scanning the PCM is a good idea. It can store pending codes that do not illuminate the MIL.

04crewvt · Post by **04crewvt** » Sat Aug 30, 2008 5:00 pm

At this point I would rather be doom and gloom than to wish it away. I still think my issues started before I went to extended change intervals. We will see in time.

F9K9 · Post by **F9K9** » Sat Aug 30, 2008 8:30 pm

04crewvt wrote:...............I still think my issues started before I went to extended change intervals....................................

Those issues were not helped with the intervals either. We need to start another thread in NOS about this because we are not helping others to solve their problems , by debating like this. I wish Mr Purdue was still active here.

Hope the kid is doing well!

AZS10Crew · Post by **AZS10Crew** » Tue Sep 02, 2008 8:54 am

You might take a quick look at the gasket on your fuel cap. I had an intermittent SES issue on mine a few years ago. It would come on, then off again after a couple ignition cycles. When I looked close at the fuel cap there were small hairline cracks in the seal on the cap. Got a new one at Wally World and light never came back on.

roadrunner · Post by **roadrunner** » Tue May 26, 2009 6:51 pm

I think my truck is possessed. Today the SES light would start flashing then quit flashing for a while then start doing it again. It did this 10 or 12 times or more. Never did come on steady just blinking. Seemed to run fine and all sensors monitored by the Scan Gauge II seemed to be running within normal ranges. Did not throw any codes when checked. When checked while flashing Scan Gauge would read "System Not Ready". When checked after light off "No Codes Stored".
Ran fine and the only thing that seemed to correspond with the blinking light was it seemed more likely to start acting up when stopped and idling and go away shortly after accelerating to driving speeds.
New cap and rotor, plugs double platinum less than 20k, fuel filter nearly new, gas cap less than 6 months old (oem), New wires less than 20K, thermostat less than 5k ago, and no other mods to engine or emission system.
Any ideas???? Did a search and did not find problems similar to what it is doing on the site unless I missed some.

Post by **HenryJ** » Tue May 26, 2009 8:00 pm

Check your battery connections. Clean and inspect. Tight bolts does not always mean tight cables.

roadrunner · Post by **roadrunner** » Tue May 26, 2009 8:02 pm

Just installed a new battery and cables are tight and clean. Thanks Brule. Any other Ideas??

Post by **HenryJ** » Tue May 26, 2009 8:09 pm

Triple check them.
I had a guy who put in a new battery and after the third time checking and rechecking he finally figured out that the studs were bottoming in the battery. His problem was intermittent and only seemed to happen when it was warm and he was moving.

The key in your description is that scangauge shows connecting. Mine only does that after the battery has been disconnected. During a normal ignition cycle that does not happen.

Look to battery cables or connection problems. Add another ground, check for resistance , etc. That is where I would look from the clues you have presented me.

roadrunner · Post by **roadrunner** » Tue May 26, 2009 8:12 pm

Thanks Brule. Will do in the AM as the fresh air and sunshine garage is a bit dark for much fruitful investigations right now. I'll let ya know if I find anything tomorrow.

Post by **HenryJ** » Tue May 26, 2009 8:16 pm

Keep an eye to that scangauge. If it says connecting the power has been disconnected and reconnected waiting for the ignition to turn on. Place it where you can see it and wiggle things around.

roadrunner · Post by **roadrunner** » Wed May 27, 2009 8:11 pm

Well, the gremlins are hiding from me now. Ran the truck for 5-6 hours driving today and no blinking light. Scan Gauge acting normal. Checked all battery and cable connections again anyway. All clean and tight. BTW I shortened my cable bolts when I had the last battery in the truck because I had a problem with them bottoming and losing connection. Guess I'm rowing with one oar out of the water till the gremlins show their pointy little heads again.

F9K9 · Post by **F9K9** » Wed May 27, 2009 8:21 pm

Any Mallards observed over head?

roadrunner · Post by **roadrunner** » Wed May 27, 2009 8:25 pm

If I do I'll be sure to send em down to keep your hood ornament company!

F9K9 · Post by **F9K9** » Wed May 27, 2009 8:50 pm

From all I understand these codes should be stored. I know my cheapo scanner will not pick them up but, I would think they are stored and retrievable from a more advanced reader. Is there a possibility that things my have advanced since you worked at a dealer?

roadrunner · Post by **roadrunner** » Thu May 28, 2009 7:45 pm

Kinda what I thought too Reed but I put my scanner on and it shows no codes and no history codes either. It may not be a thousand dollar job but it is respectable for a 250 dollar scanner and is more advanced than the monitoring functions of the Scan Gauge.
Gremlins still hiding today and I've wiggled and cleaned and jumpered all sorts of things with no change but then if they are hiding that's to be expected anyway.

04crewvt · Post by **04crewvt** » Fri May 29, 2009 3:58 am

Does your scanner support real time information logging? Some have a way to record a few minutes worth of data when you are driving and have the issue crop up. You set it in record mode and when the light comes on start recording.

roadrunner · Post by **roadrunner** » Fri May 29, 2009 12:58 pm

Yes it does unfortunately the gremlins are still hiding. Several start and drives since original problem and no blinking light. Maybe they're afraid cause I've been carrying the scanner along for the occasion. As with most electrical/electronic problems can't fix it if it won't present but I am still watchful. Will keep you all advised of any changes or discoveries.

zatco81 · Post by **zatco81** » Tue Jun 02, 2009 10:49 am

I'm having the same problem that started this thread. Cruising at highway speed then accelerating to pass causes the SES light to flash. It's not a flicker like a bad connection, more like a steady pulse. Let off the gas and the light stops. I never really thought much about it until I just read that my engine may blow up...WTF??

roadrunner · Post by **roadrunner** » Tue Jun 02, 2009 8:37 pm

Zatco, Mine's similar but opposite when it bothers. Blinks at idle or light throttle then goes out under moderate to heavy acceleration. Several more drives and still the gremlins are hiding. Frustrating but the scanner is ever present.

roadrunner · Post by **roadrunner** » Wed Oct 14, 2009 6:44 pm

Blasted blinking ses gremlin is back with a vengeance! Had several bouts with it today. No codes stored and unable to detect anything with scanner that would point to a specific problem. Finally on a steady drive with truck running hot straight and normal on highway light came on steady. Read code P0304 cleared it. Light came on steady again read it P0151 cleared it light stayed off. Pulled #4 plug as related to 304 code. All looked normal. Wires are new as is cap and rotor. (less than 10k miles on them) Ran out of daylight to do more. Will have to do more checking as time and weather and daylight permit tomorrow or the next day.
Every time the light came on was at idle when stopped at a mailbox or stop sign. Light always quit blinking and went out under moderate to heavy acceleration. Noticed exhaust very stinky at idle when light was blinking as well.

04crewvt · Post by **04crewvt** » Thu Oct 15, 2009 4:52 am

Possibly the fuel injector sticking open too long causing to go rich?

killian96ss · Post by **killian96ss** » Thu Oct 15, 2009 12:34 pm

Sounds like a bad pre-cat or too much fuel is being dumped into the engine.
A flashing SES light means that damage is being done to the catalyst system.
This could be cause by a bad pre-cat that is plugged up, or too much fuel (rich) is fouling up one of the cats.
When my CC had a similar problem it turned out that my fuel injectors were leaking so GM replaced the whole system with the newer updated multi point system.

Steve

roadrunner · Post by **roadrunner** » Thu Oct 15, 2009 12:42 pm

Today displayed a code P0300. Cleared it and other than blinking a couple different times stayed off. Not a plugged pre-cat as it is gone. I hate to think it may be fuel system as that's usually expensive but at this point may be the most likely culprit. Not to mention at 101+k GM isn't going to warranty anything in that category. This would also fall in line with the stinky exhaust and poor fuel economy when it's bothering as noted on scan gauge.

killian96ss · Post by **killian96ss** » Thu Oct 15, 2009 2:44 pm

Along with the failed injectors I mentioned above, my CC also had the P0300 code stored. I believe P0300 is the "random multiple misfire" code.

Steve

roadrunner · Post by **roadrunner** » Thu Oct 15, 2009 3:41 pm

Indeed it is the code for random multiple mis-fire. Sounds like I'm headed down injector road whether I like it or not.