Engine management light and identified faults

[Mr Bigglesworth]

Hi all,

Driving along (doing nothing special) around town my engine management light came on. Car (cupra) is still going, but sometimes there's a bit of a funny revving going on after startup for about a minute.

I got a fleabay cable (trying to save some quids rather than go straight to a garage to see if it was something simple) and ran VAG COM and got:

3 Faults Found:
17705 - Pressure Drop between Turbo and Throttle Valve (check D.V.!)
P1297 - 35-00 - -
17545 - [Long Term Fuel Trim Add.Fuel,Bank1 System too Rich ]
P1137 - 35-00 -
17834 - [Tank Vent.Valve Open ]
P1426 - 35-10 - Intermittent
Readiness: 0000 0000

(I've added the [..] from the search as I'm only using a shareware version at the mo.)

Do you think all these faults going to be related? Or are these seperate issues?

Can anyone please give me some advice on what's best - can I do any further diagnostics to check what's up (on searchs so far I'm thinking DV, MAF or some pipe) or time to go down a garage?

Cheers

info added: Oh and should add car was purchased from dealer (2nd hand 02 model with 60k miles) - dealer did full service including cambelt/waterpump. Dealer was a bit of an idiot (car's brakes caused it to fail MOT so he tried to charge me for new discs until I spotted its MOT failure online!) so would rather not have to go back to him. Have had no problems since with the car.

 

[swilky23]

try clearing the codes take it for a drive an see what comes back. with you not having the car long they may be old faults that have been fixed an not cleared off. might be worth a go anyway. if any come back look them up on ross tech for more info on possible causes/solutions. http://wiki.ross-tech.com/index.php?title=Category:Fault_Codes&from=02071

 

[DAN T]

just two days a go i got the same faults , two of them
17705 - Pressure Drop between Turbo and Throttle Valve (check D.V.!)
P1297 - 35-00 - -
17545 - [Long Term Fuel Trim Add.Fuel,Bank1 System too Rich ]
P1137 - 35-00 -
change my split-R dv back to standard bosch for now and clear the faults
today check again with VAG-com and not coming up again this two faults i hope they will not come back
but i got brake light switch where i see is a common fault no brake lights i will try to change the switch tomorrow if any carparts shop are open to buy the switch

 

[Mr Bigglesworth]

Just to be clear - when I got the car there was no engine management light.

Ok, a few more details on the progress - I cleared the faults, then went on a visit to the in laws which takes me about 50 miles on the M1 - couple of things I noticed

- feel the pull isn't as good, turbo seems weak.
- feel the engine is noisier
- feel the revs are higher (say about 200 higher - was at 3100 instead of 2900 when in 6th gear at (dashboard) c. 80mph)

One thing (and I am a novice at this) is that I've been unhappy with the last tank of tesco super I put in - seems to have been rubbish on the fuel economy - could a rubbish tank of fuel trigger off some of this? I stuck in 30l of V-power last night. Will go and do an updated VAG reading later and report back.

 

[kegger]

Where abouts are you on M1? This could be all sorts of things... might just have to be a process of elimination. If you don't wanna take it to the dealer (sounds like it might be right)... there might be a cheaper specialist near you.

 

[vee_dub_modder]

you have a negative deviation in boost pressure between the turbo and inlet. sounds like a leak, this is poss also why your running rich but 1 thing at a time...

get some carb cleaner (or wd40) and spray around all the boost/vac pipework (around dv/pipework, all the boost pipework rount the top amnd bottom of the engine bay to the cooler and inlet. you should hear a change in engine note at idle (engine speed will drop for a sec) when you find it. if you have no joys there get the cooler pressure tested, may be a pin hole in that?

tank vent is vac controlled so poss find your leak in the pipework there?? maybe.

let us know how you get on.

 

[Mr Bigglesworth]

Great info guys, I'll try this and let you know, just ran another VAG COM and only got one error btw:

1 Fault Found:
17705 - Pressure Drop between Turbo and Throttle Valve (check D.V.!)
P1297 - 35-10 - - - Intermittent
Readiness: 0000 1001

 

[vee_dub_modder]

ignore the readiness checks DTC. once you've fixed the fault and cleared codes the ecu will perform readiness checks... look it up under search. its nothing to bother about.

 

[Gezz]

The higher revs sounds like soemthing I had a few months ago, my Thermostat had gone.

it through up all sorts of error codes. The main thing to look at is the temp guage as it won't get off the bottom easily and car runs on the choke all the time, so higher revs and uses more fuel. Mine would idle at 2000rpm if I stopped it and immediately restarted it.

It also put my emissions light on.

Can also leave the car running and feel the 2 pipes running in and out of the radiator, they should both get hot until the thermostat opens and cools the car.

 

[vee_dub_modder]

Great info guys, I'll try this and let you know, just ran another VAG COM and only got one error btw:

1 Fault Found:
17705 - Pressure Drop between Turbo and Throttle Valve (check D.V.!)
P1297 - 35-10 - - - Intermittent
Readiness: 0000 1001

the above is not associated with coolant system

 

[Mr Bigglesworth]

you have a negative deviation in boost pressure between the turbo and inlet. sounds like a leak, this is poss also why your running rich but 1 thing at a time...

get some carb cleaner (or wd40) and spray around all the boost/vac pipework (around dv/pipework, all the boost pipework rount the top amnd bottom of the engine bay to the cooler and inlet. you should hear a change in engine note at idle (engine speed will drop for a sec) when you find it. if you have no joys there get the cooler pressure tested, may be a pin hole in that?

tank vent is vac controlled so poss find your leak in the pipework there?? maybe.

let us know how you get on.

Hi all, just thought I'd run an update on the situation.

I tried the above with some WD40 , tightened the odd screw on a hose a touch, though didn't notice much on the change in idle speed. Sprayed round near the DV and also round the throttle body valve. One thing I need to go back and re-check is the oil breather hose.

However, the car seemed to have improved running by itself with the only change being that I've used up the Tesco Super that was in there and been using Shell V-Power. Pull on the car did seem to have improved, however, I was still getting the fault code relating to DV pressure drop. So I do wonder if this may have been triggered by a dirty batch of fuel.

Did a fuller scan using VAG COM and found several other faults such as a radio one and also:

01039 - Coolant Temperature Sensor (G2)
30-10 - Open or Short to B+ - Intermittent.

Now my car was doing a stutter after startup so I thought I need to do the sensor change. Searched on these forums and found a guide so changed the sensor. That fault has gone, and also for the first time after a (short) drive the turbo pressure drop fault hasn't come back.

I really need to do a longer drive to check it out, but normally it comes back very quickly even on a short drive.

So could the temp sensor have been throwing out some faulty readings which was causing the car to adjust other mechanics and causing the DV pressure drop error?

Other things I think I will defo do is a throttle valve clean as found a good guide for that http://uk-mkivs.net/forums/t/127279.aspx?PageIndex=1. In due time maybe a MAF sensor clean too. Then I want to do an ECU reset at that point since I only got this car 6 months ago and it might benefit from losing previous drivers driving style!

What do you folks think?

 

[Mr Bigglesworth]

Further update - did around 30 miles mixture of town and 50mph A roads, still no sign of the of the turbo DV fault and mpg seems to have improved markedly.

Could the turbo DV fault be cause by a faulty CTS and/or a bad tank of petrol?

 

[Mr Bigglesworth]

Just an update and more help required.

Basically I did around 400 miles, including some nice A roads round north Wales, no sign of the turbo fault.

Then did around 200 miles, and at some point on the motorway I felt as though the turbo wasn't kicking in - sure enough when I checked it at home it had the intermittent turbo fault and the running rich error again.

Cleared it and did around 300 miles yesterday and had no sign of it so it is really intermittent. I need to do a throttle body clean and align, going to have a recheck of some hoses and maybe under some clips as well as try to get to the oil breather pipe which I still haven't managed to check.

I finally took the opportunity to do some logging so would someone please be able to tell me if these are normal (did MAF, N75, N249):

Group A:	'002			
	 Idle speed	Engine load	Inj. period	Air mass in
TIME	700-820 rpm	15-25%	       2.0 - 4.0 ms	2.0-4.5 g/s
STAMP/min         	   %	               ms	      g/s
				
0.36   2160	18.8	2.38	9.58
1.56   2200	37.6	4.42	16.44
2.77   2160	12.8	1.7	4.97
4.18 	2120	15	2.04	6.81
5.59 	2280	87.2	10.2	42.75
7	2800	130.8	14.96	72.81
8.2	3360	132.3	14.96	83.22
9.41	3840	127.1	14.28	95.03
10.82	4400	129.3	14.96	110.75
12.12	4920	129.3	15.98	122.11
13.44	5400	115	15.3	91.5
14.64	5360	11.3	1.7	15.08
16.05	5800	134.6	19.04	147.94
17.46	6240	126.3	17.68	150.92
				
534.62	1640	66.9	7.82	25.56
535.82	2800	81.2	9.18	43.92
537.15	3960	53.4	4.08	31.39
538.64	2840	63.2	9.18	39.75
539.95	3560	137.6	14.28	92.11
541.26	4720	131.6	14.62	119.06
542.57	5760	136.1	16.66	152.78
543.79	6440	82	7.14	91.25
545.18	4520	34.6	3.06	20.25
546.4	4920	124.1	13.26	121.94


Group B:	'115			
	Engine Speed	Engine Load	Spec. Boost	Actual Boost
TIME	700-6800 RPM	 15-150%  	990-1800 mbar	<=1800 mbar
STAMP/min	              %	               mbar	     mbar
				
0.76	2160	30.8	990	1000
1.96	2200	28.6	990	1030
3.27	2120	13.5	990	1010
4.68	2120	30.1	990	1000
6.09	2440	108.3	1720	1440
7.4	3000	131.6	1730	1750
8.6	3520	133.1	1660	1690
9.91	4040	127.1	1700	1670
11.22	4600	130.1	1690	1670
12.52	5080	129.3	1690	1660
13.83	5400	9.8	990	1210
15.16	5480	132.3	1730	1720
16.56	6000	129.3	1630	1640
17.96	6160	10.5	990	1170
				
535.02	1960	77.4	1230	1120
536.24	3240	75.9	1060	1320
537.65	3360	12	990	1100
539.05	2800	84.2	1650	1250
540.46	4040	127.8	1670	1620
541.68	5040	130.8	1660	1600
542.97	6080	135.3	1610	1700
544.27	5440	11.3	990	1130
545.6	4680	86.5	1270	1390
546.91	5080	124.8	1360	1500


Group C:	'117			
	Engine Speed	Throt Pos   	Throt Drive	Spec. Boost
TIME	700-6800 RPM	0-100%     	  0-100%	     990-1800 mbar
STAMP/min	             %	             %	            mbar
				 
0	2120	6.3	4.7	990
1.16	2160	25.1	11	990
2.36	2160	0	4.3	990
3.67	2120	10.6	4.7	990
5.08	2160	59.6	19.2	1560
6.6	2640	100	100	1720
7.8	3160	100	100	1700
9	3680	100	100	1670
10.31	4240	100	100	1690
11.64	4760	100	100	1690
12.93	5240	100	100	1700
14.24	5320	0	7.5	990
15.64	5640	100	100	1700
16.96	6080	100	100	1630
				
535.42	2320	43.5	24.3	1100
536.73	3720	44.7	23.5	1070
538.14	2600	0	5.1	990
539.45	3120	100	98.8	1670
540.86	4400	100	100	1660
542.17	5480	100	100	1680
543.39	6360	100	100	1590
544.68	4680	0	7.1	990
546	4760	63.5	34.5	1420
547.31	5200	37.6	92.2	990

Does this look normal on all three counts (1.8T, 180bhp 02 model btw)

 

[LEE69]

Use the code tags

STAMP /min % ms g/s STAMP /min % mbar mbar STAMP /min % % mbar
0.36 2160 18.8 2.38 9.58 0.76 2160 30.8 990 1000 0 2120 6.3 4.7 990
1.56 2200 37.6 4.42 16.44 1.96 2200 28.6 990 1030 1.16 2160 25.1 11 990
2.77 2160 12.8 1.7 4.97 3.27 2120 13.5 990 1010 2.36 2160 0 4.3 990
4.18 2120 15 2.04 6.81 4.68 2120 30.1 990 1000 3.67 2120 10.6 4.7 990
5.59 2280 87.2 10.2 42.75 6.09 2440 108.3 1720 1440 5.08 2160 59.6 19.2 1560
7 2800 130.8 14.96 72.81 7.4 3000 131.6 1730 1750 6.6 2640 100 100 1720
8.2 3360 132.3 14.96 83.22 8.6 3520 133.1 1660 1690 7.8 3160 100 100 1700
9.41 3840 127.1 14.28 95.03 9.91 4040 127.1 1700 1670 9 3680 100 100 1670
10.82 4400 129.3 14.96 110.75 11.22 4600 130.1 1690 1670 10.31 4240 100 100 1690
12.12 4920 129.3 15.98 122.11 12.52 5080 129.3 1690 1660 11.64 4760 100 100 1690
13.44 5400 115 15.3 91.5 13.83 5400 9.8 990 1210 12.93 5240 100 100 1700
14.64 5360 11.3 1.7 15.08 15.16 5480 132.3 1730 1720 14.24 5320 0 7.5 990
16.05 5800 134.6 19.04 147.94 16.56 6000 129.3 1630 1640 15.64 5640 100 100 1700
17.46 6240 126.3 17.68 150.92 17.96 6160 10.5 990 1170 16.96 6080 100 100 1630
18.76 4680 12.8 0 9.42 19.16 4040 12.8 990 1040 18.36 5440 0 7.8 990



534.62 1640 66.9 7.82 25.56 535.02 1960 77.4 1230 1120 535.42 2320 43.5 24.3 1100
535.82 2800 81.2 9.18 43.92 536.24 3240 75.9 1060 1320 536.73 3720 44.7 23.5 1070
537.15 3960 53.4 4.08 31.39 537.65 3360 12 990 1100 538.14 2600 0 5.1 990
538.64 2840 63.2 9.18 39.75 539.05 2800 84.2 1650 1250 539.45 3120 100 98.8 1670
539.95 3560 137.6 14.28 92.11 540.46 4040 127.8 1670 1620 540.86 4400 100 100 1660
541.26 4720 131.6 14.62 119.06 541.68 5040 130.8 1660 1600 542.17 5480 100 100 1680
542.57 5760 136.1 16.66 152.78 542.97 6080 135.3 1610 1700 543.39 6360 100 100 1590
543.79 6440 82 7.14 91.25 544.27 5440 11.3 990 1130 544.68 4680 0 7.1 990
545.18 4520 34.6 3.06 20.25 545.6 4680 86.5 1270 1390 546 4760 63.5 34.5 1420
546.4 4920 124.1 13.26 121.94 546.91 5080 124.8 1360 1500 547.31 5200 37.6 92.2 990

 

[DAN T]

i had about the same faults m8 , when i was going in rediness it show me cat faild o2 sensor .
panic for nothing and change coil packs ,spark plugs and still the same running in limp mode.
once i change the temp sensor clear the faults it sort it self out and my car is running like a dream now.
i bought genuine temp sensor from seremotors .

 

[traumapat]

i think you need to paste it into excel or similar. should be easier to read.

the check dv code is common and usually points to a leak.... not heard it flag over a coolant sensor though.. 2 issues? boost leak will affect mpg.

the other possible could be a dying MAF sensor. it rarely throws any fault but will affect mpg. next time the car runs poorly try disconnecting the MAF sensor and if its instantly better... theres a good chance its the issue.

be a good idea to install a boost gauge as youll see if its performing right or holding back.

 

[Mr Bigglesworth]

i think you need to paste it into excel or similar. should be easier to read.

the check dv code is common and usually points to a leak.... not heard it flag over a coolant sensor though.. 2 issues? boost leak will affect mpg.

the other possible could be a dying MAF sensor. it rarely throws any fault but will affect mpg. next time the car runs poorly try disconnecting the MAF sensor and if its instantly better... theres a good chance its the issue.

be a good idea to install a boost gauge as youll see if its performing right or holding back.

Ta for all the quick replies LEE69, DAN T and traumapat (esp the code tags hint!)

So the above code contains a MAF log and I was hoping this would mean something to someone here in terms of if the MAF is performing as it should be.

In terms of diconnecting the MAF etc, I think it is sooo intermittent that its going to be hard to notice if it made a difference - maybe if it starts struggling more I'll try that. Will look into a boost gauge (any links for more info as not aware of that?).

 

[DAN T]

all i mean is sometimes hard to find what it is going wrong, i ve been told the car is running with mini volts and it can come up with those faults. i was panicking big time not know what is going on ,if the temp sensor is coming as a fault just recommended to change and go from there.
as i said from that in my car come up with emission light and all sorts of faults .
i hope it will help, i know is to many opinions here now u may get confused but try and see witch may do for u the job
cheers

 

[Mr Bigglesworth]

all i mean is sometimes hard to find what it is going wrong, i ve been told the car is running with mini volts and it can come up with those faults. i was panicking big time not know what is going on ,if the temp sensor is coming as a fault just recommended to change and go from there.
as i said from that in my car come up with emission light and all sorts of faults .
i hope it will help, i know is to many opinions here now u may get confused but try and see witch may do for u the job
cheers

I know, too many options of what it can be. The temp sensor change did really help with the general running of the car, but there are still a few other niggles that are hard to pin down!

 

[Mr Bigglesworth]

This is a saga that prob don't interest many - but ever since I did a MAF clean and a TB clean, including putting the piping back on quite tight (it seems to have slipped down the TB a touch), cars been running really well. Must have done >600 miles and no sign of any fault codes on my engine.

For that matter I actually don't have a single fault code on the car fullstop at the moment having sorted out my rear tweeter and several other problems.

That is except my rear brake light bulb has just gone