small problem with my gsi

[MOL]

If im driving my gsi, if i put my foot down a bit and the revs reach about 4000rpm the engine management light is coming on, and it feels like the car is holding back sometimes.
Its just mainly when i put my foot to the floor.... For example if im down the motorway and put my foot down a bit to overtake someone it does it then.

Its not continuous tho, Sometimes it comes on for 3 seconds then off for 3 seconds, then on again etc.
It seems like when more air is getting sucked in that it does it. Just mainly when i put my foot down on the throttle, I dont want this to sound as if im saying Its only when i rag the car it does it because.. I dont necesarily have to be going fast, If im going up a steep hill and put my foot to the floor even at 2 - 3000rpm it does it...
Its just mainly when i put my foot to the floor and it opens up the throttle fully. Regardless to whether im going fast or slow.

I first thought maybe the airflow metre so ive changed that, But its still doing it.

Any suggestions before I have resort to paying someone to look at it for me?

Cheers :cool:

[mikey14sr]

Blocked fuel filter or a dodgy sensor somewhere?

[Riggy]

flash the fault codes out mate and see if we can see from there

[craig green]

Check the connections on all the sensors around the engine.

Get a can of electrical contact spray (not WD40 ffs) & clean all the connectors & refit them snugly. Make sure the plug gaps are correct too (0.8mm IIRC).

You can read off the fault codes using a paper clip. Look on the Topbuzz site for how to do it.

My std GSi did it once or twice how you describe, nothing is wrong or such, I shouldnt think.

[ANDYRACER]

You changed the plugs and leads recently?

[craig green]

I dont think that would trigger the ECU light, altough the ign system can fall over if the HT circuit draws too big a current (large gaps/poor connections on leads).

[MOL]

Is the plug to check the fault codes next to the brake servo? Thats what ive just been told but havnt had a chance to look yet.
Cheers for the replies everyone.
When i do this paperclip test, Im guessing I need the engine ticking over? Or do i just turn the key over 1 click until the dash lights come up?
Or doesnt it matter either way?

cheers

[Riggy]

yeah just stick a paper clip in number 1&2 and turn ignition on then count the number of flashes :thumb:

[MOL]

Cheers mate, I'll give it a go and see how i get on :cool:

[MOL]

Just done a test it came up with......

3flashes.....then a pause......6flashes.

Anyone help with this?

Cheers :) :)

[Riggy]

http://www.topbuzz.co.uk/info/fault_codes/fault_codes.htm#gm

doesnt show a code for the multec bit strange

[MOL]

Ive also looked on here...

http://www.atpelectronics.co.uk/hinttips/fcvauxmpi.htm

And on here

http://www.atpelectronics.co.uk/hinttips/fcvaux.htm

But im not sure what im looking for... am i lookin for code 36? :confused:
Either way it doesnt show up on either of those links :confused:

[craig green]

Incorrect RON plug/damaged RON plug.

Try another from a scrapyard, or turn yours around.

Is your engine the E16SE (engine number) & Bosch/Siemens ECU.

What reg?

[MOL]

yes mate its an E16se
Its J-reg

[craig green]

Riggys link is the one you want (topbuzz).

[MOL]

Cheers for your help mate, appreciate it.

[craig green]

Apparently the ECU might not log the fault unless the light stays on for 30 secs or more. Is the car down on power or in limp home mode when it occurs?

Anything drastically wrong?

[MOL]

No nothing drastically wrong. Just feels like its holding back slightly sometimes...similar to a missfire but not quite the same (awkward to explain).
Its nothing that would stop me using the car on a daily basis anyway, It doesnt bother me too much, but like most people I like my car to be running spot on with no problems.

I was thinking that what you said above, I think the longest it stays on for is only about 5/6seconds, so it may not log the fault.

I'll take a look at the RON plug and take things from there.

[craig green]

Mine used to flash on now & again with no issues.

Only real trouble I ever had with mine was it gradually lost power once until it couldnt pull itself in 2nd gear then cut out.

I never found out what it was, after it started when it cooled down. The next day it was fine.

I had ignition troubles too, but I think I sorted that with some decent leads that fitted correctly.

They dont give any trouble tbh if they are well serviced.

[craig green]

Pinch an octane (RON) plug from a scrapyard & try it.

[MOL]

Ye mines similar to your first post. Sometimes it will flash on and there will be no difference in the drive of it.
But then other times (more at higher speeds) I can feel it pulling/holding back.

I'll pop the scrappy and try that tomorow, Cheers mate

[James P]

if the car runs lumpy at slow revs when it stationary then ur dizzy might need twisting, there's a 12mm bolt underneeth the dizzy, loosen it off then u can ajust it. keep the engine running and adjust it towards you or away. not much, a few mils. u should hear the engines revs go up, also it makes ur cars responce time faster. if its not that then cheack your air pipe, mine had a hidden split in it. or it could be your fuel lines blocked, that sometimes happens if you run ur car to low on petrol and dont have very good fillters.

hope you sort it out.

[Riggy]

turning the dizzy wont work on a gsi , its a fixed position one ,

and as for ron plugs there are loads of different coloured ones which although are both still 95 & 98 ron they are different

think topbuzz explains this aswell :thumb:

[Riggy]

stolen from topbuzz

What do these plugs do?

Their main function is to prevent detonation (otherwise known as 'pinking') when using unleaded fuel. The plug is wired into the ECU (Engine Control Unit) wire loom so that it can be fitted into one of two positions. You simply unplug the RON plug and turn it over to be another value.

Inside the plug are two different fixed value resistors. The ECU provides a 5v reference source to the RON plug connector (see figure 4). When this signal is connected to earth, via the RON plug fitted which has a resistor inside, a voltage level lower than the 5v source will be returned to the ECU. The ECU may modify both the basic timing and fuel injection maps. Hence this RON code plug will advance up the ignition at different rates. The amount of advance under load is approx. 5deg less when coded for unleaded (95) than for premium (98) leaded fuel.

What are the resistance values?

The resistance value also influences other functions and by using any of the 8 values available it is possible to make minor changes to the running of the engine.


The RON plugs come in nine different colours:

Resistance Value RON plug colour & Octane rating
Zero ohms Blue 95, Black 91
220 ohms Brown 95, Black 95
470 ohms Brown 98
750 ohms Green 98, White 98, Orange 91
1200 ohms Green 95 (part No. 90276398)
2200 ohms Yellow 95, White 95, Violet 98
4700 ohms Red 98 (part No. 90276399)
Meg ohms (Infinity) Violet 95, Red 95, Orange 95, Yellow 91, Blue 91

[MOL]

That top line makes sense now, because the car has been pinking. Looks like it should sort that.
But now it appears the problem which ive been trying to solve hasnt been logged on the ecu lol.
I'll just check air pipes and fuel lines, See how i get on doing that.

cheers

[craig green]

I'd suggest you grab loadsa RON plugs from a srapyard.

Some of them are rare (cant remember which colour) & used to be worth getting hold of.

Just experiment & see, like I said the engine & its ECU is so basic short of the cambelt snapping nothing can really go that badly wrong.

[MOL]

agree there, Whatever it is, It's more than likely something small.
It's tryna to find out what it is
Hopefully I'll sort it sooner than later tho lol

[Adam]

You can turn the dizzy to set the initial ignition timing.
Try backing the dizzy off a few degrees if its pinking.
How do you know its pinking tho? Can you hear it under load?

Ron plug is a possibility, i've Never heard of one going wrong tho.
What is the plug set to now? 95?

[MOL]

Ye, I can hear that its pinking. Im not sure what its set to.... It's not something which bothers me too much tho, as it doesnt effect the performance of the car at all.

Its the other problem with the management light coming on every now and then which is bothering me more.

Cheers

[Nazza's Nova]

have u checked the crank sensor?

[Adam]

If you are 100% sure its pinking try retarding the ignition timing a few degrees.
Pinkings quite a hard noise to diagnose tho, especially if you've not heard it before.