all confused on engine codes & engine is pinging

[illumastorm]

i am kinda new to FI engines with all the sensors on things so this is confusing. i have a 94, 2wd, 2.3L, manual. it started pinging when it's under a load (like going up a hill in 4th or 5th), is not noticable when going on flat road or coasting (which i would expect). sometimes it pings a lot, other times it is almost not noticable even on the same road at the same hills. i got a check engine light on so i followed the directions on the other web site showing how to pull the codes from the dash light and here's what i got.
33
53
35
12
14
33
23
36
35
62
14
33
now the 62 saids it's for an auto tranny and this is a manual so i am ignoring that one( probably some computer test?)
the others i have no idea on how to test the sensors, like the egr, etc. any ideas? i have done a search but haven't found much.

 

[Wicked_Sludge]

you have a few repeats in there, so for my sake i cleaned it up a little for you:

12 - IAC code
14 - PIP, profile ignition pickup
23 - TPS code
33 - EGR code
35 - EVR/PFE
36 - ?
53 - TPS code

i cant find a code 36 anywhere.

it looks to me like you have a mix of codes in there (like the previous ownder was trying to run self tests that wouldnt run or something). i would clear ALL the codes and drive the truck to see which ones come back...then deal with them one at a time.

your pinging is no doubt due to a failed EGR system. that code 33 means the system did not detect your EGR valve opening. the valve could be stuck shut, there could be a vacuum issue, or the EGR tube/intake passages could be plugged with carbon.

 

[illumastorm]

thanks, i kinda figured with that many codes that maybe the PO never did anything about replacing parts that went bad and those have been there for a while, the light was on when i bought the truck but the price was low and the light was on so i was hoping maybe it was something minor as the truck runs good except for the pinging. i cleared the codes like it says to, and i'll drive it to work tonight and check it again tomorrow morning to see what shows up.
i was pretty sure the pinging had something to so with the egr valve, i'll take it off and check it to see if it's sticking and clean any cardon off, but if it's ok and it has something to do with the sensor thing that lets vacum to the valve then that will probably have to be replaced right?

 

[Wicked_Sludge]

the little sensor is called a DPFE sensor and they do fail pretty often. if its bad then it'll need replacing...but since your truck is exhibiting symptoms of a non-functional EGR (the pinging), im willing to bet that the sensor is working properly and the EGR is stuck.

 

[illumastorm]

well i decided to take it for a drive this afternoon, and when i got back the code i got was just 33, the list says it's the egr not opening or something and also said evp, evr, & pfc, whatever those mean.

 

[Wicked_Sludge]

33 is just an EGR code...we knew that one would come back. keep an eye out for any other codes and get that EGR fixed

 

[illumastorm]

so is that just the egr valve or the sensor thing? sorry for all the questions.

 

[Wicked_Sludge]

like i said, since your truck is actually showing symptoms of an inoperative EGR, i would give the sensor the benifit of the doubt (for now anyway) and look at the rest of the system.

you can test the EGR valve by starting the truck, removing the vacuum line and applying vacuum to the valve with a pump. you should be able to see the valve move and the engine should run very rough or die. the valve should also hold vacuum (if it bleeds down its toast). if so, then the valve is OK. apart from that, make sure the 2 lines from the EGR tube going to the DPFE sensor are not blocked with carbon. also check that the EGR tube and passages inside the intake (remove the valve and inspect) are not blocked.

 

[illumastorm]

well everything seems fine, took the egr vavle off, had a little carbon built up and got it cleaned off, valve holds vacum, all hoses cleared and checked them for leaks and they all are good, passages all cleared, still have the problem so i am thinking it's the DPFE sensor. anyway of testing that or is just replacing it the only way?

 

[Wicked_Sludge]

the valve is functioning and your still getting pinging and a code huh? thats odd.

there may be a way to test the DPFE, but i dont know what it is. it is a somewhat high failure item, so theres a decent chance that its the problem. though usually a failing DPFE trips a CEL without any EGR symptoms.

 

[Earl43P]

Lot of EGR info here: http://www.tomco-inc.com/techinfo.aspx