OK now I am at that point... OBDII keeps repreating the same code over and over again P1313 - Misfire and poss damage to catalyst yada yada.... and sometimes the light will flash as if it were recognizing a current misfire yet the truck runs like a dream except for at idle when it has just a slight slight little bump for a miss. So far I have done Plugs and Wires... Cleaned MAF sensor....cleaned throttle body.... and Performed Induction...( Cleaner ran through vaccum port directly into Plentium ).... Yet it has come back again... And always comes back after clearing it but stays off for like a day maybe 2... Seems to come back after my starter seems to poss stick?? i.e. makes grinding noise and stumbles all over it self and sounds absolutly nothing like the typical Disco 1 starting.... yet I dont want to condem starter if thats not the problem... Now where??? :banghead:
Repeat Offender - P1313!!!!
- Thread starter RamRod
- Start date
seafoam will cause p1313. does it come back on its own after a couple days or is it after you run cleaner through plenum?
NO the code was there well before I did any work... Before plugs, wires, sea foam.... and even after all that the code still appears
ptschram
Well-known member
OK, we have a misfire on the left bank.
It is not the MAF, it is not the fuel pump, it is not the starter.
On a '97 Disco, I would say the most common cause for this is a sticking exhaust valve. Next on the list is a clogged or improperly spraying fuel injector, worn camshaft, etc.
Let's take a look at fuel pressure with key on and then ten minutes after key turned off. If we find a significant loss of fuel pressure over this period of time, we have presumptive proof of a bad injector.
When the truck is started, at idle, is it making any untoward noises?
PT
It is not the MAF, it is not the fuel pump, it is not the starter.
On a '97 Disco, I would say the most common cause for this is a sticking exhaust valve. Next on the list is a clogged or improperly spraying fuel injector, worn camshaft, etc.
Let's take a look at fuel pressure with key on and then ten minutes after key turned off. If we find a significant loss of fuel pressure over this period of time, we have presumptive proof of a bad injector.
When the truck is started, at idle, is it making any untoward noises?
PT
ok ill test fuel presure right now give me like 30 mins..... but untowed noises?? can you explain what kind of noise that is?
Ok vehicle is definatly not loosing fuel presure so that is going to eliminate the leaking fuel injector so now where to?
Fuel Presure with key on is at 37p.s.i. dropped slightly while pump was actually on like 3 p.s.i. only....with key off Fuel presure stayed at 35 p.s.i. did not drop after about 10mins....
Fuel Presure with key on is at 37p.s.i. dropped slightly while pump was actually on like 3 p.s.i. only....with key off Fuel presure stayed at 35 p.s.i. did not drop after about 10mins....
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ptschram
Well-known member
OK, let's now move to ignition. Pull the plugs and look them over. We're looking for differences in one plug or another compared to the rest of them. While we have the plugs out, let's run a compression checjk to rule out valve problems.
Untoward noises. Ticking, knocking, tapping, arcing, anything out of the ordinary.
You say the truck has 185K miles, you imply you just got the truck, is this correct? If so, we have little to no knowledge of past maintenance. Let's hope this is something that can be fixed externally and we do not need to do a headjob, nor replace the cam.
Untoward noises. Ticking, knocking, tapping, arcing, anything out of the ordinary.
You say the truck has 185K miles, you imply you just got the truck, is this correct? If so, we have little to no knowledge of past maintenance. Let's hope this is something that can be fixed externally and we do not need to do a headjob, nor replace the cam.
Alright no stuck valve... replaced all plugs last week, pulled out all again today and none of them appear majorly diffrent also performed compression and every cylinder has good compression... You think it could possibly be a fuel injector not opening??? Cause there def not leaking as per test this morn... but if there not pulsing that would not show I need to check the pulse all of them shouldnt I??
And no... no untoward noises...everything runs / sounds good only has that stupid slight miss at idle... as soon as I throttle it goes away
And no... no untoward noises...everything runs / sounds good only has that stupid slight miss at idle... as soon as I throttle it goes away
Scratch that.... I think it is a burned exhaust valve or four... I pulled plugs on the left bank and they looked like they were only getting a partial burn.... like it wasnt burning all the fuel it needed to... so PT from here is it a def head job or just get the long block????
ptschram
Well-known member
OK, we're getting somewhere, but let's make sure we know just where we're going before we begin the journey!
We now know that our problem is limited to one bank of cylinders... Gee, what could it be? In a GEMS truck, about the only thing in common from one bank to the next is the oxygen sensor... Let's swap the front sensors from left to right and see if the sooting of the plugs follows the sensor.
PT
We now know that our problem is limited to one bank of cylinders... Gee, what could it be? In a GEMS truck, about the only thing in common from one bank to the next is the oxygen sensor... Let's swap the front sensors from left to right and see if the sooting of the plugs follows the sensor.
PT
Should I leave the same harness plugged into the same o2 or swap those as well .... also is the ecm designed like a nissan which I am sure it is... If I unplug the o2 sensors does the ecm of a fixed fail safe setting it automatically goes to??
RamRod said:
The harness will remain the same as it was. PT is just having you switch sides with the sensors to isolate whether or not one of the sensors is bad. If the problem follows the sensor then bango you have isolated the problem. If it doesn't then it's back to troubleshooting.
RamRod said:
Got the head gaskets done but it still leaks and burns water. She is tetering between a new engine and a sawzall. I either have a slipped liner a cracked block or a cracked head. I hate to kill her dead but I also don't want to dump a lot of cash into a hole.
The good news is that I just installed new motor mounts and a new roto flex. They both worked great to get her out of my sight before I killed her dead.
Now everyone keeps saying sway out rotoflez for greaseable u-joints... I already have greaseable u-joints so does that mean previous owner already did the swap??
Oh......Not trying to change the subject either but I ran outa time last night to swap o2 sensors.... I will do it this morning as long as I can get a bay opened
Oh......Not trying to change the subject either but I ran outa time last night to swap o2 sensors.... I will do it this morning as long as I can get a bay opened
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ptschram
Well-known member
RamRod said:
We are trying to determine if the oxygen sensor response on one sensor is bad. Disconnect the sensors from the harness, remove the sensors from the exhaust, swap the sensors side to side, then connect to the corresponding harness.
If you leave them attached to the wiring harness, it will show if there is a difference with the engine exhaust characteristics, but not the sensor response.
PT