I said i'll be back!

[Laird Scooby]

Originally Posted by Stephen Edwin

This will be academic for me unless a need arises. I am, interested, a little.

There has been reference to yellow injectors. I suspect that might be the Bosch injector offered by parts suppliers for my B200F. And as you say that would be the same for your car. Possibly the part Volvo would specify/supply now. Or would you say Volvo parts supply what you have fitted? Oh well it doesn't matter.

I see your arithmetic. Re furbishing the old injectors costs about the same as buying an entire new injector. And you got a good deal on a set of six secondhand. Cushti.

It would be interesting if the injectors were available, to compare a set of good condition single squirt to a set of good condition four squirt, in the same car. But at these costs who can realistically afford that?

I've seen references to yellow injectors, if they're the ones i'm thinking of, they are the high-flow variety favoured by the "boosty-boys" who have increased the level of turbo boost and consequently need to increase fueling to suit.
Going back to my old SD1 days, when the V8 EFi became more affordable to those who wished to modify it, i seem to recall green injectors were the "go to" injectors for high flow rates to meet the fueling needs of big valve, high compression, gas-flowed, ported and polished heads and wild camshafts.

Something in the back of my mind says these green injectors flowed 440cc/min @ 3bar fuel rail pressure which is a bit over double what the injectors in ours flow (200cc/min) so gives you a rough idea.

I described (somewhere, maybe not on this thread) the response with the replacement injectors as "having a wall of torque now". I took a friend for a spin in the car earlier, he's known the car as long as i have as he took me to collect it and has been in it countless times. Therefore his opinion is very relevant as he's known all of the improvements i've made.
His comment was long the lines of "Wow! I see what you mean about the wall of torque, instant response now as well!"

Bear in mind he had just got out of a Lexus LS430 which has something like 290bhp and 420Nm (about 315lb/ft in real money), most things would feel flat and gutless by comparison.

[Stephen Edwin]

Dave,

I've followed your lead in buying a Gunson Gastester. The green "professional" one. Looks a good example. Should be interesting to explore the B200F with it.

I'm still curious about those injectors. How much your jam jar's improvement is due to the change of injector type. There must be some, possibly a lot, of improvement due to at least one old injector having a questionable squirt when you removed and inspected.A bit like a faulty spark plug or HT lead come off the spark plug. Especially as your six cylinders would smooth things out over any defect.

I might dig around to re formulate the question. I asked between what Volvo would specify and what you have fitted.

Greater torque sounds grand. But it is only curiosity unless I get a seriously good price for injectors.

[Laird Scooby]

I think the green one has the digital display doesn't it? Same as mine, just with a different readout - one of the models also has tach, volts and a few other useful ranges built in but i can't remember.

Knowing what the car drives like with a FUBAR HT lead on one pot and the improvement renewing all the HT leads (from the USA) made, the injectors have surpassed that.

As for what Volvo would recommend - probably irrelevant - Bosch made the injectors and the system. Bosch no longer make the 0 280 150 734 that were fitted.

It doesn't help that Boschs website doesn't list the old Volvo stuff so i had to look for other vehicles that used the same injector originally.

Enter a 1989 Peugeot 405 1.9i "decoy" :

https://www.boschautoparts.com/en/auto

That originally used the same 0 280 150 734 injector as well. This is the Bosch recommended replacement :

https://www.boschautoparts.com/en/au...n?partId=62534

Look at the various photos of the injector and you will find the part number on it - 0 280 156 045 which is exactly what i bought for mine. They are the newer version with 4 pintles of what is essentially the same injector.

However, when i put the Gastester on it this afternoon i had some very odd results! Half expected but will explain more in a later post!

[Stephen Edwin]

Yes digital. Not always an advantage. Time will tell.

So far as I can see: CO, two ranges of Tach, dwell in per cent or degrees including dwell variation with engine speed, volts. Dwell variation said to be useful with injection engines?

Handy to have tach under the bonnet e.g. when checking the air mass meter. Yes I have a separate multi-meter to measure voltage "spike" across pins so far as I remember the test.

Information always aids diagnosis. Time spent on reconnaissance is never wasted, as a retired army officer told me when I was young.

[Laird Scooby]

I'm guessing it's this one then :



Ginsons don't appear to list it anymore, just the digital version of mine, the G4125 :

http://www.gunson.co.uk/product/G4125/



I think you'll find the dwell function is for the ignition dwell and is read using the probes on the coil LT terminals. Might be wrong but that's how my Megger Automotive Multimeter works, one of the first digital jobbies and a lot of money when new!

You might be able to measure the dwell on the ignition (and maybe injectors too) but it will only give you an indication what's happening - you won't be able to alter it.

[Stephen Edwin]

Yes .... the green one init !!!

And yes. The blurb only suggested the dwell reading would give an indication of how the engine is "performing" shall we say.

"In the olde days" I used a dwell meter to check after setting points. But yes I could then further adjust the points if necessary. Times move on.

[Laird Scooby]

As i hadn't checked the CO after fitting the new injectors, today gave me a good time to check it. Took the car for a spin with the Gastester in the back, warming up on my jump-pack.

Calibrated it before starting :



Then shoved the probe up one of the tailpipes :





Then the electric cooling fan kicked in :





Next, i tried something else :





That's a tad high at 6.7%! Only to be expected as i'd pulled the vac hose off the FPR and plugged it - first so i could check the FPR would richen the mixture when vacuum was removed, second so i could check for any fuel leaking from the FPR and third to eliminate the FPR from the process of working out why the CO level was now much higher.

Refitting the vacuum hose, i turned my attention to the thermostatically controlled flap valve on the air cleaner. Given it was a warm day today, i would have expected the flap valve to mainly pull air from the colder side, not from the hot side where air is passed over the exhaust manifold first.

Wasn't happening that way, i removed the hot air trunking from the air filter end and noted the CO dropped by at least 1% - difficult to say exactly how much over that as the cooling fan kicked in again.

Then i looked at the mixture screw on the MAF. In the past, someone had drilled two holes in the plug on it and when i checked the CO for the MoT last year, it didn't need adjustment. Normally they won't need adjustment unless something is out of kilter somewhere so this got me thinking.

As the CO level drops and the engine runs extremely lean, this can push the HC content up a lot. My guess is that over successive years with the old injectors getting a bit worse each year that the HC level went up due to some cylinders (those with the duff injectors) weren't firing properly so each year, the mixture was tweaked richer until the duff cylinders were running right.

Now all the injectors are squirting better, this is no longer a problem and the CO ends up higher than it should be.

After turning the screw on the MAF 7 1/2 turns anti-clockwise, i finally got there :



As a final check that the calibration hadn't wandered or been knocked by me :



Yes, i know - it's only at 1.8% in that pic and should be 2% for the air calibration point but first it had swung there pretty quickly and experience with this Gastester tells me it does that then the last little bit can take a few minutes and secondly, by the time i'd shut the bonnet etc and come back, it was up to bang on 2% so i know i finally reached 1% approximately.

Driving home, the car felt even smoother and livelier but in a more progressive way. I'd done a 0-60 run on the way there, using a stopwatch app on my phone which i can reach without taking my hands off the wheel. On the way there, i got about 11 secs - not good!

On the way back, i did another but had forgotten to reset the stopwatch! It came up somewhere around the 8 second mark although i can't be too sure. As such i did another after resetting the stopwatch. Even after fluffing the start, i still got 0-66 in 9.47 so 0-60 would have been mid to low 8 seconds.

This concurs with how it felt during the 0-60 on the way to where i checked the CO - it felt good up to a certain point then felt like it was overfueling.

Anyway, aside from a precautionary check before the MoT, unless any other anomalies show up i think that's it on the fuel front for now!

[Stephen Edwin]

That is very interesting details Dave.

Is FPR = fuel pump relay, but, I can't make that idea fit the context of what you are saying. Or is that the different engines?

MAF adjusting screw? MAF as in otherwise called air mass meter? Gosh there's no adjusting screw on my 240 air mass meter !!!!!

Good luck with the MOT. Mine is soon now. I don't try to completely check the car. I pay the tester to do that for me. But famous last words if there's an issue it is usually something simple to fix and obvious that I have overlooked.

Insomnia EDIT: I'm still not happy with myself that, one year there was a not quite profile matching tyre on the same axle. EEK. Ye gods !! The tyres are one's only grip to the road !!! Well that should not happen this year, all tyres are less than a year old of the same good quality make and size and profile init !!!

.

[Stephen Edwin]

Originally Posted by Laird Scooby

..... This is the Bosch recommended replacement :

https://www.boschautoparts.com/en/au...n?partId=62534

Look at the various photos of the injector and you will find the part number on it - 0 280 156 045 which is exactly what i bought for mine. They are the newer version with 4 pintles of what is essentially the same injector.

....

As matter of price, I see that injector is £45.61 inc VAT at e.g. buycarparts.co.uk

Total order over £140, "free" i.e. included shipping.

Three times that cost you quoted for refurbishment?

There might well be better deals, like wot I guess you got Dave. And possibly worse deals too.

.

[Laird Scooby]

The acronym "FPR" is very commonly used to denote the Fuel Pressure Regulator Stephen - this is mine :



There's a photo in the Haynes BoF that shows the location of the mixture screw :



This is my MAF/AMM :



I was more interested in getting the part number in case i couldn't get the CO level down (suggesting a fault within the MAF) as i had wound out 7 1/2 turns on a 10-turn multi-turn potentiometer that was already 1 1/2 turns out from its inner stop before i started.

That makes a total of 9 turns, not leaving much adjustment left!

Taking that into consideration, it suggests the old injectors were flowing so badly that it made the engine lean enough to cause excessive hydrocarbons (unburnt fuel) or HC as it appears on the emissions sheet at MoT time. I suspect over the years the mixture has been tweaked a little at a time to keep it running right, compensating for ever worsening injector performance.

Your FPR will be as shown in these photos Stephen :





More or less dead centre in that photo, radiator end of the fuel rail, slightly obscured by that large black hose for the air conditioning. That looks like a left hand drive B230F but the only difference will be the engine capacity., the FPR will be in the same place.