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Engine swap/replacement on my 1998 VFR800 (bad engine, curious on any tips and tricks)


VicSev93

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5 hours ago, Halfrider said:

Hey vfrcapn, what fork, front wheel, triple clamp combo are you running?

Many thanks

RC51 SP2, whole front end. There are several threads here on the conversion.

 

Back to hissing valves now...

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Hello all! I remembered that my friend had sent me a photo of the wiring, here it is. I honestly dont know which module is where on here, and what's responsible for what function, but perhaps you guys can take a look and give me some hints. Most of these wires do look pretty corroded, chewed. etc. (I should have started this thread with this photo) lol

121455363_756447811584435_6870554414517150666_n.jpg

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As daved has mentioned below, the Bank Angle Sensor wiring in the middle needs attention.

Again what is the status of your Fi Light. Are you getting any malfunction codes?

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5 hours ago, Grum said:

??

Hey Danno can you enlighten me. What is XRW-GHW wire? Never heard of this before!

sorry, just random wire since I don't have actual test from manual in front of me.

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38 minutes ago, DannoXYZ said:

sorry, just random wire since I don't have actual test from manual in front of me.

Well, I hope the OP who appears to be struggling with the situation wasn't as confused as I was and went through the whole Service Manual and circuit diagram as I did trying to find the "random wire" you mentioned to measure battery voltage on.!!!

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2 hours ago, VicSev93 said:

Hello all! I remembered that my friend had sent me a photo of the wiring, here it is. I honestly dont know which module is where on here, and what's responsible for what function, but perhaps you guys can take a look and give me some hints. Most of these wires do look pretty corroded, chewed. etc. (I should have started this thread with this photo) lol

121455363_756447811584435_6870554414517150666_n.jpg

Looks like something has been chewing on the wires going to your tilt switch?

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9 minutes ago, daved said:

Looks like something has been chewing on the wires going to your tilt switch?

Good pickup I just thought it was all dirt, but on closer inspection those wires do look like they've been nibbled at, needs to be closely looked at and repaired. Could well cause an intermittent engine shutdown. Have mentioned to the OP to monitor the voltage at the ESR which would identify a possible issue with the BAS should that voltage suddenly go missing.

Wonder what else might have been bitten into?

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Cobwebs are surprisingly efficient at conducting electricity, you need to clean the lot out

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UPDATE! Hello all! some interesting developments today. As was mentioned here, we cleared the present codes, went for a ride (bike still died, twice) and checked for codes again. only 4 came up! this was 1, 2, 8, 9. Checked what it meant, it had to do with electronics 1 and 2 deal with the MAP sensor. 8 and 9 with TP and IAT. took out the multimeter and got to work. Here were the results, the IAT and TP sensors are dead. The same goes for the MAP sensor. Can this be the reason, that when I let off the throttle, the bike just dies? When I did go for a ride today, I was able to cover maybe 5 blocks, with throttle always remaining open at 3-4k rpm. Once I let off the throttle the bike shut off. At least now there is a lead to the issue, or I really hope so.. 

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No wonder you have issues! The common thing between the MAP, TPS, IAT is the Geen/Orange wire being Signal Ground. Check this wire for continuity back to the ECM B2 for each of the sensors. If that's ok check all Grounds for the ECM.

Hmm maybe your hungry mice have been dining on more wires?

Do a close inspection of your earth block located in the wire harness above your chain guard, can cause multiple ground issues.

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^^^ What Grum is pointing out above is more likely than all 3 of those sensors being bad.  Can those sensors fail?  Yes - but very unlikely all 3 have bitten the dust.  Check grounds  as outlined above 1st, if necessary repair, treat with Oxgard and then see what you have.  Early on in my 6th gen ownership I separated every connector I could get to and applied Oxgard to every pin combo using a toothpick.  Seems to have kept the electrons moving.  Best of luck with it. 

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11 hours ago, Grum said:

No wonder you have issues! The common thing between the MAP, TPS, IAT is the Geen/Orange wire being Signal Ground. Check this wire for continuity back to the ECM B2 for each of the sensors. If that's ok check all Grounds for the ECM.

Hmm maybe your hungry mice have been dining on more wires?

Do a close inspection of your earth block located in the wire harness above your chain guard, can cause multiple ground issues.

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Grum! Thank you so much man, and thank you everyone for their input! My friend has checked everything as you have mentioned, everything looks good. There is an odd problem now, He checked the codes again, and only the MAP sensor code came back. However, we think this is the case, because the air box is not screwed down with 4 screws as its supposed to be (the bike came without them when we bought it, and a K&N air filter, so the sensor is probably just catching unregistered air going in. Thing is...now I'm really lost. Since only 1 code came back. Such an odd issue.

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Make sure the vacuum hoses to the MAP sensor are all good, make sure all vacuum hoses are all properly connected and there are no vacuum leaks anywhere on the bike. Check the electrical connection to the MAP sensor is clean and good.

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2 minutes ago, Grum said:

Make sure the vacuum hoses to the MAP sensor are all good, make sure all vacuum hoses are all properly connected and there are no vacuum leaks anywhere on the bike. Check the electrical connection to the MAP sensor is clean and good.

Will do first thing in the morning! 

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Hey all! Here is a video of the bike starting and dying (dies at 1:50 seconds) Its as if the engine just slowly dies off.. The progress we have made so far, is that it finally starts without giving it constant throttle and holding the ignition switch, It can now start by itself. (perhaps its because we cleaned, and checked the modules on which the fault codes were showing) But as you can see at 1:50. It just decides to die. Any ideas?

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Try monitoring the Fuel Pump 12v supply voltage on the Brown wire from the Fuel Cut relay. Does this voltage disappear just prior to the bike dying. Also check for clean good connections to the fuel pump connector under the tank. Make sure the fuel pump Green ground wire is properly grounded.

 

Also as mentioned you want to be sure the 12v for all your EFI stuff is good coming from the Engine Stop Relay, on the Black/White wire. Make sure this is solid 12v and should be there with Ignition Switch to On. Check this also while engine is running, you don't want to see any voltage drop occurring.

 

Have you had a very good inspection of your Main Fuse B 30amp. It can suffer badly from high resistance burnt wiring, causing voltage drop and strange effects.

 

Again! Have you confirmed your charging voltage is ok?

 

And as a possible side issue - Repair the chewed wires to your Bank Angle Sensor per your photo.! Check your whole bike over for chewed wires!!!

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Again, problem is electrical and you will NOT be able to fix it until you pull out multimeter and measure voltages at various parts of circuits.
 

No one can help you until you report actual measured voltages at specific areas. Starting with areas Grum pointed out. It’s like going to dentist or doctor and they ask you where it hurts and you say,

“it just hurts”!
“Can you tell me where it hurts?”.
“It just hurts!”

”but where does it hurt?”

”It just hurts!”

”does it hurt inside? Does your hands hurt? Or your feet hurt? Or your teeth?”

”It just hurts!”


Not very helpful in diagnosing issue without specifics.

Here’s guide on using multimeter.

 

https://learn.sparkfun.com/tutorials/how-to-use-a-multimeter/all


in addition to measuring power going Into to fuel-pump, you need to measure flow-rate out of pump at operating pressure. There’s no way to guess that pump is operating properly.

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@Grum:

 

Thank you very much for all your help, I'm the other guy associated with this bike.  I checked all the grounds I could find and sanded down oxide all bolt on contacts to make sure theres a good connection. The ground collector plug is good, I don't see anything that can cause issues here. I cleaned everything with electronics cleaner and checked continuity, we're good here.

121732506_650822985618804_43534719684847

 

I have also repaired the BAS wires, they are good and solid now. There are still some wires that are damaged, but they're on the 10A light circuit. As I understand they should not cause any issues in regards to running even if they short. They are on the list for repair though.

 

The 30A main fuse is good, I looked at it and checked with a multimeter, don't see anything with it that can cause issues. I'm going through and cleaning all the contacts and connectors for everything.

 

@DannoXYZ: I will check flow rate and the other things Grum mentioned in the previous post.

 

@mello dude: Checked compression with a compression tester, front left cylinder has 60psi dry, 120 wet. front right has 120 dry, 150 wet. rear two have 155 psi both dry.

 

 

 

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And to be clear, I have no delusions the running issue is solely the engines fault. There is some electrical issue in this bike. However 1 cylinder is confirmed toast and another is almost toast. This bike will need a new engine or a top end rebuild regardless of solving this electrical issue

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Yes, as previously mentioned, at least two independent issues. With engine-issues contributing 0%, NOTHING to your running issues. Engine can actually run on 3-cylinders and redline just fine (33% of #2 and 66% of #4 ). Having +80bhp will still make it faster than majority of bikes on road. I've run bikes with holes blown through pistons and hardly noticed anything other than slightly down on power at 100% WOT. That's because when you're cruising down road at 100kph, it requires only 10bhp, which 50cc scooter engine can make. Not being able to go above 2000rpms and redline and randomly dying is completely 100% electrical issue. Mechanically, absolutely nothing else can cause this unless you've got an entire eagle's nest and babies stuck in airbox.

 

Electricals are far worse of problems and contributing to your issues 100%  Unless you've got x-ray vision and can see electrons flowing in wires, you have no idea if a wire actually conducts electricity or has internal corrosion and breaks. So you still need to take measurements and come up with numbers.

 

1. unplug ECU connector and measure resistance of BAS wires from end-to-end. It may look OK, but can be corroded or broken internally. Only way to really confirm functionality is measure resistance end to end of each wire. Even worse is shorts, which requires measuring resistance of each wire relative to ground. A 2nd-set of numbers for exact same wires.

 

2. Testing sensors. What procedure did you use to confirm IAT, ECT is OK? Again, need to measure and post resistance at specific temperatures. At ECU connector to verify wiring in between is good.

  2a. What is resistance of IAT at room temperature?

  2b. What is resistance of IAT at 100C in boiling water?

  2c. What is resistance of ECT at room temperature?

  2d. What is resistance of ECT at 100C in boiling water?

  2e. What is resistance of IAT & ECT wires between ECU and sensor connector?

  2f. What is resistance of IAT & ECT wires to ground?

 

3. MAP sensor, very common source of issues:

  3a. Key ON, what is reference-voltage going into MAP sensor?
  3b. Key ON, bike OFF, what is output-voltage of MAP-sensor at ECU connector?

  3c. Key ON, bike idling, what is output-voltage of MAP-sensor at ECU connector?

  3d. Even better is calibration testing with vacuum pump. What is output-voltage at 100kpa?, 80kpa? 60kpa? 40kpa?

  3e. Also measure actual engine-vacuum going to MAP-sensor at idle. What's vacuum amount MAP-sensor sees when engine is idling? Does vacuum stay constant or does it drop off? What is vacuum just before engine dies?

 

4. TPS-sensor

  4a. Key ON, what is reference-voltage going into TPS sensor?

  4b. Key ON, bike OFF, what is output of TPS-sensor with closed throttle?
  4c. Key ON, bike OFF, what is output of TPS-sensor at WOT throttle?

  4d. What is resistance of idle-switch with closed throttle?
 

5. fuel-pump power-supply. Bike idling, what is voltage going into fuel-pump? Does it stay constant up to point of bike dying?

6. engine-stop relay, blk/white. How many volts does it have with key ON? How many volts with bike-idling? Does it stay constant up to point of bike dying?


ECU error-codes only points to errors in a system with many parts. ECU detects that MAP-sensor is sending errorneous incorrect data and throws code. That does not meant that ONLY MAP sensor is bad. It may be fine, but wiring in between can be bad. Or vacuum-hose may have leak. Or reference-voltage may be off. So you need to measure and come up with numbers for each and every individual component of system to actually troubleshoot MAP-sensor error-code. Same with all other systems throwing code.

 

Every single number gets you closer and closer to solving this problem. Some basic measurements: http://www.nissantechnicianinfo.mobi/htmlversions/Fall_2011/Voltage_Drop_Resistance_Measurement.html

Electricity actually flows on surface of wire, thus need to have many strands to increase surface-area for flow. When you've got corrosion on surface of wires, even with wire still solid underneath, it'll impeded electrical flow. Conditions that can be detected with measurements and numbers below.
 

You have not posted a single number. Thus you are as far from solving this as when you started. There may even be some oscilloscope testing with analysing waveforms in your future.

 

image014.jpgimage010.jpg

pic-8529597550837213789-1600x1200.jpeg

uc?export=download&id=1j3uQp5QFlVmvjN8di

uc?export=download&id=1ur36Ro0ulFOexwFT_

uc?export=download&id=1iEpjs9Q6OFgMTk4Dw

 

 

I actually fired a mechanic from my shop because he refused to measure. Instead, wasted an entire day swapping out entire fuel and ignition system. If I had a nickel for every time a "fuse looks OK" but actually didn't conduct any electricity...

 

uc?export=download&id=1dyN84fesyTMjYK32w

 

 

 

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2 hours ago, DannoXYZ said:

1. unplug ECU connector and measure resistance of BAS wires from end-to-end.

Wow that's a great lot of info there Danno. But just a small thing, the Bank Angle Sensor (BAS) has no connection to the ECU. It just provides a ground to the ESR engine stop relay, provided the bike hasn't fallen over. So if the main EFI power on the Black/White or the Fuel Pump voltage is ok, then the BAS will be working.

But these voltages and grounds for the ECU and Fuel Pump do need checking.

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15 minutes ago, Grum said:

Wow that's a great lot of info there Danno. But just a small thing, the Bank Angle Sensor (BAS) has no connection to the ECU. It just provides a ground to the ESR engine stop relay, provided the bike hasn't fallen over. So if the main EFI power on the Black/White or the Fuel Pump voltage is ok, then the BAS will be working.

But these voltages and grounds for the ECU and Fuel Pump do need checking.

Hey, thanks for clarification! I just found the VFR800 diagram. It's such clever design that BAS, similar to kickstand and neutral-safety switches . 🙂

 

Now this is binary thing right? If BAS was at fault or its wiring, bike wouldn't run at all?

 

I had an issue with BAS on my CBR600RR, where it was sticking internally at an angle. So it would never ground output and bike wouldn't start. Every couple years in cold winter, I'd have to take it off and shake it around a bit to get innards aligned properly and then bike would start properly.

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When you get the engine out,  it would be intetesting to see the front cylinders with the head off and find out what has happened to it. In the video there does seem to be some sort of ticking sound that doesn't seem normal.  Someone really had to pound on / abuse that thing to damage it badly in just 15,000 miles. 

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1 hour ago, DannoXYZ said:

Now this is binary thing right? If BAS was at fault or its wiring, bike wouldn't run at all?

Correct. ESR cannot energize = Totally dead EFI system.

Subtle difference between a faulty BAS and Kill Switch which both control the ESR, is that a faulty BAS will allow you to crank the engine over, it just will not start. Faulty Kill Switch = No Cranking as well as ESR not energizing.

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Thank you very much for your very detailed posts, I see the saying still holds true "the best way to get the right answer on the internet is not to ask a question; it's to post the wrong answer"

 

I will come back with concrete numbers 😀

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