TPS ?

[Darrin]

Hi all. Having a bit of bother getting the Vee to start and idle. Bit of backgroud  info. Bought the bike last November and it ran fine. Have since completly stripped it and put it all back together. As soon as I could I started the enginge and all was OK. Adjusted the throttle bodies and also the tps and all was fine. The only thing I have done to the engine is adjust the valve shims.

 Last week took the bike for an MOT and when I initially started it it would not run without holding open the throttle. The only diferance this time is that it has fresh fuel. Ran very  lumpy and there was lots of smoke coming out of the exhaust. Any way switched it off and tried again and all was fine as it had always been before. So took it for the mot and came back. The bike then sat for a few days until this Sunday just gone and when I wen to start it the problem was back. Would not idle and sounded like it was misfireing. Checked that both plugs were sparking and they were but they were wet with fuel. Put it in to the dealer mode and initially no codes came up, but the C14 TPS came up. So undid the screws but no matter where it was turned to all you could get was C00 with the high bar only. Did disconect the battery first to see if that would clear/reset anything. All it did was clear the C14 code.

So today I have got and fitted a new sensor but it is still exactly the same. C00 with a high bar only. I know that these can take a short while to register so when I have moved it I do wait a fair while, but nothing.

So any suggestions would be greatly received.

[Sven]

This sounds very similar to the problem that Bumhead has had on his Vee. He's had idle & mis-fire problems for the last 6 months on his. Seems to have sorted it by setting the TPS but not as it says in the manual. From what I understand he just adjusted it until the engine ran OK. When he set it by the book, it ran crap!!
Sorry I can't be more helpful - I'll see if I can get hold of him, he can probably explain it better.

[greywolf]

Check the wiring first. If the wiring to the TPS is okay and you can't get the bar centered at idle, replace the TPS. They are known to sometimes fail.

[Bumhead]

PM sent  

[kevshek]

Don't keep us in suspense, is there a fix for thus? Come on, cough it up

[Darrin]

Hi Greywolf, have checked the wiring for both voltage at the connector and also continuity. I have fitted a new tps but still cannot get the bar to move from the high setting no matter where the tps is positioned. So at the moment am stumped.

[greywolf]

The TPS is basically a potentiometer or variable resistor. It has three wires, red, pink/white and black/brown. The red also connects to the TOS, APS, STPS, IAPS and ECM using crimp connectors in the harness. The P/W goes directly to the ECM. The B/Br connects to the ECTS, STPS, IATS, IAPS and ECM using crimp connectors in the harness. If any of the crimp connectors has a marginal connection, the ECM will get the wrong info from the sensors.

I think what I would do in your situation is to check the ECM connector since that was not done yet. If it is alright, check the resistance between the TPS and ECM connectors of the same color. If the resistance is not basically zero red to red and B/Br to B/Br. I would add a jumper to bypass a marginal connection rather than hunt for a bad crimp connector.  P/W to P/W is direct and shouldn't be a problem but checking it should give a value the other two should meet.

[greywolf]

I forgot the connections from the ECM to the odometer, or clock in 2004 and later models. The bike could have a proper TPS setting and display the dash position wrongly if there was too much resistance in those connections.

[Juvecu]

This might sound daft, but double check that you are working with the TPS and that you don't have it confused with the STVA sensor perhaps.

[Darrin]

Yes I am adjusting the tps.

Have already checked the wiring as best as I can and all seems OK.

Have taken off the throttle bodies today to check out the boots and all vacuum pipes and all of these are OK. Also checked the fuel filter and fuel deilvery, both OK. Only thing I can't measure is the fuel pressure but there definately seems to be good pressure. Am going to try a new set of spark plugs even though the ones that are in there now are only a couple of months old. It has also been suggested that even though I have bought a new tps that may be faulty. So will see how the spark plugs go and if still no joy will see if Suzuki will change the tps for another one.

Must admit starting to get a little annoyed now.

[Darrin]

An update as   hopefully this will help someone in the same situation.

Bike is now up and running and all is OK.

The initial problem when the tps failed was the bike would not idle/run due to the fuel injection system overfueling as the tps had failed. Now I can only assume that this had damaged the spark plugs due to the amount of additional fuel going in to the cylinders. Believe me when I say it was an awful lot of fuel. Bumhead knows what I mean as his did the same.

Now after fitting the new tps the bike would still not run. Now it was Bumhead who did say to change the plugs which I did today and the bike started up straight away. Set up the tps and tookit out for a run and can report all is fine.

So the morale of the story is even though something may be new (the spark plugs were only 1 month old) it does not mean to say they will be OK. They did still spark and look to be fine, but for the sake of a few pounds it was a cheap thing to change. When I look back at the amount of time and effort in to trying to sort this and it was just down to a coupleof spark plugs.

Anyway thanks to Bumhead for the chat and at least mine was sorted a little quicker than yours, but at least we are both now back on the road.

Thanks all.

[Sven]

Glad to hear its all sorted.

[Bumhead]

Glad you are all sorted and yes, yours was done considerably quicker than mine


Now get out and enjoy your bike )  )

Now its time to sell some spare parts that I now Have!