Hey guys, new to owning a Seat and hope to get it sorted

[danny1204]

Dunno if anyone can put a finger on a couple if issues I'm having. Got my leon as a non runner due to fuel pump but that got sorted in a couple of days, but since then have had eml warnings for egr and map sensor, both of which I've swapped out and still getting issues, I know a simple code reader ain't gonna diagnose deep issues and waiting to get the car deep read for codes. Now its come up with a fuel trim bank one code. Would this be an air/vacuum leak, or could it be like the garage have said, a lambda sensor that's on uts way out? Some folks have even said coolant temp sensor, so I'm blagged, I don't mind swapping out parts but dint wanna be doing it unnecessarily. Sorry for the long winded post, just pulling out what's left of my ever thinning hair

 

[CosmicBlue]

Just swapping parts out won't fix the issues on their own. The car's ECUs will have errors written into them - you'll need a tool like VCDS or OBD11 Pro to clear the error codes before you'll know for sure.

 

[mty12345]

Hi Danny welcome to the forum. It's Matt here from FB who recommended you to join.

It's a difficult one as you've not had it long and have so many different issues, but first off ignore the temp sensor suggestion. That could cause it to struggle to start when very cold, or when the engine is hot, but you said it was stalling at junctions etc in your FB post didn't you? If so then the the temp sensor wouldn't cause that sort of thing.

Is the fuel trim code for bank1 too rich, or for bank1 too lean? I'll assume it's too lean for now as that's by far the most common. That means that the engine is either not getting enough fuel, or sucking in unmetered air (Intake/PCV/Vacuum leak)

Have you got a basic code reader capable of showing fuel trim numbers as live data? If so, then have a look at the data from your long term fuel trim (LTFT) . If it's an intake/pcv leak, then the number should be high at idle, and then start to get lower if you rev the engine and hold it at 3000rpm for 15 secs or so.

If there is no difference between idle and revving it, then it's most likely not enough fuel pressure. In that case is the new pump picking up ok? No leaks around the fuel pressure regulator etc? Either that or more likely a PCV leak. The rubber and plastic PCV hoses are getting old now, and they very often split if not replaced. A big split in a PCV hose could cause stalling, rough idle and high positive fuel trims, so that would be the number one suspect IMO

Hope that makes sense and is some help, any questions or anything that doesn't make sense, fire away

 

[danny1204]

Just swapping parts out won't fix the issues on their own. The car's ECUs will have errors written into them - you'll need a tool like VCDS or OBD11 Pro to clear the error codes before you'll know for sure.

Cheers for the input, gonna get the bits done then get it on to a full diagnostics computer then go from there. It's absolutely wrecking my head.

 

[danny1204]

Hi Danny welcome to the forum. It's Matt here from FB who recommended you to join.

It's a difficult one as you've not had it long and have so many different issues, but first off ignore the temp sensor suggestion. That could cause it to struggle to start when very cold, or when the engine is hot, but you said it was stalling at junctions etc in your FB post didn't you? If so then the the temp sensor wouldn't cause that sort of thing.

Is the fuel trim code for bank1 too rich, or for bank1 too lean? I'll assume it's too lean for now as that's by far the most common. That means that the engine is either not getting enough fuel, or sucking in unmetered air (Intake/PCV/Vacuum leak)

Have you got a basic code reader capable of showing fuel trim numbers as live data? If so, then have a look at the data from your long term fuel trim (LTFT) . If it's an intake/pcv leak, then the number should be high at idle, and then get lower if you rev the engine and hold it at 3000rpm for 10 secs or so.

If there is no difference between idle and revving it, then it's most likely not enough fuel pressure. In that case is the new pump picking up ok? No leaks around the fuel pressure regulator etc? Either that or more likely a PCV leak. The rubber and plastic PCV hoses are getting old now, and they very often split of not replaced. A big split in a PCV hose could cause stalling, rough idle and high positive fuel trims, so that would be the number on suspect IMO

Hope that makes sense and is some help, any questions or anything that doesn't make sense, fire away

Hi matt, thanks for the recommendation, I'm gonna have a serious look into the pipes toward the intake tomorrow albeit the weather allows me, can't stand the rain haha. I'll check all the pipe work and go from there. Will try get the basic code reader I've got on tonight and see if I can check trim on that. The new fuel pump sucks away like a good un and can hear it going strong. I would have thought if it was a clogged filter it would be sgit at any rpm, least that's what I get with the bike which is a dinosaur now too.
I'll get on it tonight hopefully and post back here if any news either way.
Thanks again bud

 

[mty12345]

Hi matt, thanks for the recommendation, I'm gonna have a serious look into the pipes toward the intake tomorrow albeit the weather allows me, can't stand the rain haha. I'll check all the pipe work and go from there. Will try get the basic code reader I've got on tonight and see if I can check trim on that. The new fuel pump sucks away like a good un and can hear it going strong. I would have thought if it was a clogged filter it would be sgit at any rpm, least that's what I get with the bike which is a dinosaur now too.
I'll get on it tonight hopefully and post back here if any news either way.
Thanks again bud

No worries mate, hope you get it sorted soon. I agree about the filter, petrol is usually so clean that they can go years without blocking, but if you can't find any other reason then may be worth changing anyway as they are less than £10.

I forgot to mention the lambda sensor. That could be a cause as well, but usually you would get a code specifically for it. In my experience a lot of garages often default to it being the MAF or the Lambda when they don't know how to diagnose it. A lot of places are excellent mechanics, but very poor at diagnosing stuff.

 

[danny1204]

No worries mate, hope you get it sorted soon. I agree about the filter, petrol is usually so clean that they can go years without blocking, but if you can't find any other reason then may be worth changing anyway as they are less than £10.

I forgot to mention the lambda sensor. That could be a cause as well, but usually you would get a code specifically for it. In my experience a lot of garages often default to it being the MAF or the Lambda when they don't know how to diagnose it. A lot of places are excellent mechanics, but very poor at diagnosing stuff.

 

[danny1204]

I'll try find filter somehow haha and give that a looking over. Yeah I checked the lambda on the reader and its within tolerance so it shouldn't be that although have ordered one anyway
I have sent the video of the reading on to the fb comments that we were on earlier, I'm not sure what's going on with it to be fair, but if you see that video hopefully it makes sense to you more than me. Will try vet a look at pcv and the pressure sensor on the fuel rail too, the clamps look past their best but can't see where pressure would be leaking but you never know

 

[danny1204]

New lambda sensor came this morning. Got it on and no difference. Is the pcv the round thing at the bottom of the intake at the back of the engine as you look at it? Also had a split pipe that leads into air intake beneath throttle body, sealed that but still no better.
Getting bank 1 trim code and map sensor code still too

 

[GORDYDJ]

Hi Danny welcome to the forum. It's Matt here from FB who recommended you to join.

It's a difficult one as you've not had it long and have so many different issues, but first off ignore the temp sensor suggestion. That could cause it to struggle to start when very cold, or when the engine is hot, but you said it was stalling at junctions etc in your FB post didn't you? If so then the the temp sensor wouldn't cause that sort of thing.

Is the fuel trim code for bank1 too rich, or for bank1 too lean? I'll assume it's too lean for now as that's by far the most common. That means that the engine is either not getting enough fuel, or sucking in unmetered air (Intake/PCV/Vacuum leak)

Have you got a basic code reader capable of showing fuel trim numbers as live data? If so, then have a look at the data from your long term fuel trim (LTFT) . If it's an intake/pcv leak, then the number should be high at idle, and then start to get lower if you rev the engine and hold it at 3000rpm for 15 secs or so.

If there is no difference between idle and revving it, then it's most likely not enough fuel pressure. In that case is the new pump picking up ok? No leaks around the fuel pressure regulator etc? Either that or more likely a PCV leak. The rubber and plastic PCV hoses are getting old now, and they very often split if not replaced. A big split in a PCV hose could cause stalling, rough idle and high positive fuel trims, so that would be the number one suspect IMO

Hi. I probably should start my own thread. But as you understand fuel trims I thought you might be able help. And of course, apologise for butting in on this thread.

I have been using the Torque pro app for several years. on my previous cars it was clearly limited to what it could display based on number of available sensors.
I currently have a 2009 Leon 1.9TDI. For some reason it's not displaying the fuel trims on torque. On the whole it does show a lot less than on the older cars (and OBDEleven). Expected to see more. It's showing things like fuel flow rate, coolant temp, throttle position and CO2/Km. So I don't think it's the dongle. I'm still getting used to OBDeleven and can't so far find readings relating to fuel trims etc.
TIA