Idle Stumble/relay

[nose2wind]

I know some discussion has occured about a stumble at idle on some of the v-11s.

Mine has developed this trait. If the idle is set low it may quit,otherwise it will pick back up. It seems as though it is electrical in nature. Has their been a consesus as to what causes this?

 

I had a problem before where I would be crusing at 4-5000 and it would cut out and back on, just like if you hit the kill switch off and on fast. Eventually it left me stranded and I traced it back to the ECU relay. This feels the same but at idle. Maybe I should change some of the relays ECU and Injectors.

 

Any advice welcome.

 

Does anyone know the relay # that can be found a radioshack etc.?

 

Thanks

[Tom M]

Replace all of your relays with these for about $15 total and you'll never have to wonder if you're having relay problems again.

 

http://www.dpguzzi.com/relay.htm

 

The stumble at idle could be due to the throttle bodies being out of sync. How long since they were last balanced?

[nose2wind]

Replace all of your relays with these for about $15 total and you'll never have to wonder if you're having relay problems again.

 

http://www.dpguzzi.com/relay.htm

 

The stumble at idle could be due to the throttle bodies being out of sync. How long since they were last balanced?

 

I bought a twinmax and did them myself last year. I think they are fine. One thing I have never checked is the TPS. Could this cause a stumble? The bike has 45,000 miles. My theory is that maybe one of the relays ECU or Injectors is breaking contact causing this problem but I don't know why it would just do it at idle. I will switch those 2 relays and see what happens.

[richard100t]

I bought a twinmax and did them myself last year. I think they are fine. One thing I have never checked is the TPS. Could this cause a stumble? The bike has 45,000 miles. My theory is that maybe one of the relays ECU or Injectors is breaking contact causing this problem but I don't know why it would just do it at idle. I will switch those 2 relays and see what happens.

If you have checked and/or adjusted your valves since the last time you balanced the tb's you need to hook the twinmax back up and take a look.

[Guest ratchethack]

Hey Dawg -- does it seem to be dropping an occasional single beat at idle or trailing throttle ONLY -- not under load? If so, it may be due to a little chain whip on the cam chain. It's not serious. I've had this since Day 1, and so've many others. Being in a good state of tune overall, set to idle at ~1100 RPM, and well broken in will all help to keep it from stalling when it does this.

[nose2wind]

Hey Dawg -- does it seem to be dropping an occasional single beat at idle or trailing throttle ONLY -- not under load? If so, it may be due to a little chain whip on the cam chain. It's not serious. I've had this since Day 1, and so've many others. Being in a good state of tune overall, set to idle at ~1100 RPM, and well broken in will all help to keep it from stalling when it does this.

 

You are stopped at a light just sitting no hand on throttle, Idle on tach around 1000 rpm. It will stumble 1 or 2 beats go back up to 1000 mis again and smooth out. Then it will be fine for awhile. The rpm usually will start to rise a little the longer you sit. It is somewhat un predictable. Sometimes if the idle gets low enough it will quit. I have since raised it some. I did the TB balance after plugs valve adjust etc. The only thing I have never done since new is TPS.

 

Hope that helps.

 

I might add the bike runs great at speed. A little popping at off throttle.

 

I have Pod filters,Stucchi crossover, Mistrals, Powercomander usb with his map for my setup. I thought about increasing the mix manually in the low range on the PC if it is maybe to lean.

 

d

[Alex-Corsa]

You are stopped at a light just sitting no hand on throttle, Idle on tach around 1000 rpm. It will stumble 1 or 2 beats go back up to 1000 mis again and smooth out.

 

That sounds like a sync problem to me.In your case I would sync again , in addition unscrew-remove the bypass air screws at the TBs and clean them a bit and put back in.

They get some dirt from time to time and need to be cleaned. So does sync, I do sync or sync check on my bike precautionary and as an short of "breakfast practise" (when I have nothing else to do).

Anyways a fresh sync can only be good.

TIP , you won't hve to unscrew the TPS pot. from allen screws to adjust when the TBs re connected. Just screw-unscrew the cup-spoon like conecting to the right TB (underneath from the TB connecting bar) Use one plier to hold the connecting rod and the other to adjust (screw-unscrew) the "spoon"

Doing these tuff correct then you will know that any throttle popping will be most possiblly from the mapping

[Guest ratchethack]

You are stopped at a light just sitting no hand on throttle, Idle on tach around 1000 rpm. It will stumble 1 or 2 beats go back up to 1000 mis again and smooth out. Then it will be fine for awhile. The rpm usually will start to rise a little the longer you sit. It is somewhat un predictable. Sometimes if the idle gets low enough it will quit. I have since raised it some. I did the TB balance after plugs valve adjust etc. The only thing I have never done since new is TPS.

 

Hope that helps.

 

I might add the bike runs great at speed. A little popping at off throttle.

 

I have Pod filters,Stucchi crossover, Mistrals, Powercomander usb with his map for my setup. I thought about increasing the mix manually in the low range on the PC if it is maybe to lean.

 

d

Dawg, you're in pretty good shape, IMHO. I can only tell you wot I'd do, and keep in mind this is just me. My Guzzi runs so well I can't imagine how it could possibly run better (except for the very occasional miss at idle or off throttle ONLY, and I hardly notice it), and no one else has ever touched it. I've got the same bike as yourself, with just about exactly the same mods and setup, only real difference being intake. I'd get the idle up to ~1100 RPM and set the TPS the way I've always done it, which is the way Todd Eagan (Dynojet Rep) has always recommended doing it for Guzzi's with PC III installed: With TBs linked, set TPS to 500-525 mV between top and bottom pins.

[docc]

My tach is 300 rpm optomistic so at an indicated 1000 it's idling at 700 rpm. Not happy! Setting the idle to an indicated 1300 settles lots of this stumbling and cough.

 

My early Sport also smoothed out at idle and just off idle with the carbon cannisters removed. The experts disagree whether this could make any difference, but this was my experience.

 

By 45,000 miles I would think a thorough tune with a careful TPS adjustment is in order. Check out Jeff in Ohio's tune up procedure. Your Guzzi will thank you!

[nose2wind]

Dawg, you're in pretty good shape, IMHO. I can only tell you wot I'd do, and keep in mind this is just me. My Guzzi runs so well I can't imagine how it could possibly run better (except for the very occasional miss at idle or off throttle ONLY, and I hardly notice it), and no one else has ever touched it. I've got the same bike as yourself, with just about exactly the same mods and setup, only real difference being intake. I'd get the idle up to ~1100 RPM and set the TPS the way I've always done it, which is the way Todd Eagan (Dynojet Rep) has always recommended doing it for Guzzi's with PC III installed: With TBs linked, set TPS to 500-525 mV between top and bottom pins.

 

Does todd have a procedure written out on this? Do you remember which wires on the ECU? I would confim this on mine.

[Guest ratchethack]

Does todd have a procedure written out on this?

Not to my knowledge. There are several written by others both here and at GuzziTech.com, however.

Do you remember which wires on the ECU? I would confim this on mine.

Dawg, the wires are pretty easily traced from the TPS to the ECU. Many check the voltage at the ECU. I found that the easiest way was to wire in a simple "semi-permanent" solution whereby I can take TPS readings any time.

 

The solution I came up with is to back-probe the connector at the TPS with 2 short lengths of bell wire shoved directly through the protective boot into the connector, with insulated female spade connectors on the ends of the 2 wires, which I've looped back and zip-tied in place on the TPS connector itself. To check the TPS, I stick the multimeter probes in the spade connectors, and Bob's y'er mother's brother.

[nose2wind]

Not to my knowledge. There are several written by others both here and at GuzziTech.com, however.

 

Dawg, the wires are pretty easily traced from the TPS to the ECU. Many check the voltage at the ECU. I found that the easiest way was to wire in a simple "semi-permanent" solution whereby I can take TPS readings any time.

 

The solution I came up with is to back-probe the connector at the TPS with 2 short lengths of bell wire shoved directly through the protective boot into the connector, with insulated female spade connectors on the ends of the 2 wires, which I've looped back and zip-tied in place on the TPS connector itself. To check the TPS, I stick the multimeter probes in the spade connectors, and Bob's y'er mother's brother.

 

I tried to check the TPS setting last night. I haven't backed of any of the screws yet just wanted to see what reading I would get. I traced the wires even have 2 at the connector. Turn on the ignition but not started.

I get nothing. I'm not sure how to set the volt meter. I don't see a Mv scale. I set it at DV volts one has 3 scales 0-10,0-50,0-250. It has V-mA next to the scales. I'm not sure this is going to work when I try to set the 500-525. The V dial has 4 positions 10,50,250,500 and a side with mA .5, 50,250

 

I have another meter that reads 4 scales 0-3 up to 0-1200. the dial .06,3,15,60,300&up

 

Any suggestions?

[dlaing]

Two tight of valves might cause this problem

 

Clearance specs from the owners manual: intake: 0.004" (0.10mm), exhaust 0.006" (0.15mm) I think that is too tight.

 

I like mine set to 0.006"(0.15mm) intake and 0.008"(0.20mm) exhaust.

 

RaceCo recommends 0.008"(0.20mm) intake and 0.010"(0.25mm) exhaust.

 

YMMV

 

But FWIW, mine still occassionally misses at idle, and once in a great while stalls, usually after many freeway miles followed by a quick stop at a red light.

 

TPS is certainly a possibility, and you may fine it works best at a little above or below the 500-525mV at idle

Use the 0-10V scale.

I spliced into the wires so that I could get a permanent reading point from two dangling wires.

In my opinion it is better to set TPS by disconnecting linkage and "choke" and setting to factory spec.

But there is still a point of ambiguity on the resting point of a totally closed right throttle body, so perfection is subjective

The 500--525mV idle method is less accurate because the relationship between throttle openings and idle speeds vary.

But if you find you are now at say 475mV, bumping it up to 500mV could be your ticket. Likewise, if you are at 550mV notching it down to 525mV could take you to heaven.

[Guest ratchethack]

I tried to check the TPS setting last night. I haven't backed of any of the screws yet just wanted to see what reading I would get. I traced the wires even have 2 at the connector. Turn on the ignition but not started.

I get nothing. I'm not sure how to set the volt meter. I don't see a Mv scale. I set it at DV volts one has 3 scales 0-10,0-50,0-250. It has V-mA next to the scales. I'm not sure this is going to work when I try to set the 500-525. The V dial has 4 positions 10,50,250,500 and a side with mA .5, 50,250

 

I have another meter that reads 4 scales 0-3 up to 0-1200. the dial .06,3,15,60,300&up

 

Any suggestions?

Dawg, you've done things correctly as far as I can tell. Ignition on but not started. Started and running is the same, but no need. Sometimes when back-probing a connector, a little futzing helps get a solid electrical connection.

 

Modern digital multimeters have a feature that automatically adjusts for scale. If you set it at DCV, the decimal point on the display will correspond with the unit of measure, also on the display. If yours is analog, it doesn't have this feature, so you have to select the correct scale. 1V = 1,000 mV.

 

BTW - I've noticed in all the literature on reading TPS voltage that a RANGE is always given. This makes sense to me, because I find that it can vary +/- as much as 10 or even 20 or so mV, depending on lots of things.

[nose2wind]

I was reading on the TB balance and seem to find a difference of opinion.

 

One said to set the air screws to 3/4 - 1 turn out and leave them alone that they are for co setting only.

It states how to use the set stop screws for balance only.

 

The other uses the stop screws and goes back to the air screws for a final adjustments

 

Any advice on which is better?

 

Thanks