'87 505 GLS Fuel Injection System

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wadehilts

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Fellow Frogger
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Hi all,

I just purchased an '87 505 GLS with 220k miles on the odometer, I have a lot of experience working on 404s, having done a complete mechanical restoration of my 1969 404 (at age 22, I may be the youngest person in North America to have rebuilt an XC6 engine!). The 505 is new to me. I don't know if you Aussies had a similar model 505 as the US GLS model, but I'm hopeful.

It has the ZDJL 2.2L in it, and it recently was completely rebuilt. Everything new except for the fuel injection system, which is the Bosch Jetronic LU2 - i think. I am picking up the car on Saturday, but have test driven it and would like to sort out a few issues. My goal is to maximize the gas mileage and power that the car gets. Here are the problems that may be related to the fuel injection system that I am aware of:

The previous owner says that the gas mileage has dropped from 20 mpg in the city to 18 mpg in the last couple months.

  • The tachometer bounces all over - especially about 2000 rpm. It is almost useless at this point.

  • The previous owner says that the gas mileage has dropped from 20 mpg in the city to 18 mpg in the last couple months.
I found this technical document on peugeot505.info : http://peugeot505.info//files/manuals/tt-sd-nsd_15-5.pdf. This seems to be a good place to start troubleshooting, but some of the testing requires a "tachymetric bypass harness P/N 0091.94" and something tells me I'm not going to find one of those. Keep in mind, my goal here is to improve gas mileage and power if possible. Does anybody have recommendations as to what I can test? Are there any parts I should just go ahead and replace? Would a different fuel injection system with better efficiency be an option? I'm open to anything at this point, just looking to learn. I will talk to the former owner tonight, so if I should ask for any more information, let me know!
I've also found some injectors on eBay that apparently fit my 505 (they're listed as Volvo injectors), is this an item I should look into replacing?

Thanks in advance, I'm excited to promote myself to a 2 Peugeot driveway soon!
 
Good promotion.

When my 505 was young it used about 10l/100km in mixed driving. That works at about 23.5mpg (using little US gallons).

That manual was too slow downloading here, but I suspect it's the "LU2 TEST SECTION ZDJL" manual. If it's not, PM me and I can send you my copy. The tests are pretty straightforward. I'd be particularly looking at the temp sensor since it can fail, and a false cold reading could richen the mixture a lot.

Not too sure about the tacho jumping around. Probably worth investigating though as an intermittent grounding of its wire would ground the coil leaving you without spark (and probably burning out the coil too).

Tach relay is no deep mystery. The fancy harness is probably little more than a jumper wire joining two terminals on the socket.

I'd steer clear of the Volvo injectors as an unknown quantity. Perhaps getting yours cleaned would be worthwhile.

If you really want to minimise fuel consumption and maximise power, fitting an aftermarket ECU is pretty effective. I fitted Megasquirt to mine. A fair amount of work, but you end up fully understanding your EFI, mine uses about 20% less fuel, and is much more responsive. Depending on where you are, your local authorities might not approve though.

Edit: Oh, one other thing. The main harness connectors (the big ones in the engine bay) had loosened over time and various signals became intermittent -- including coolant. Could only tell this with the Megasquirt log files, but it could be a quiet problem for the L-Jetronic. Unplug the sockets and, if the connectors seem loose, nip them up a bit.

Have fun,

Rob.
 
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Hi Rob,
Thank you very much for the wealth of knowledge on this subject. You are corrrect, the LU2 TEST SECTION ZDJL manual is what I found. If I could get to the bottom of the tachometer and fuel consumption issue, that would buy me some time to plan an aftermarket ECU system. You have me very intrigued with this aftermarket ECU prospect!
I live in the USA, so I will have to pass the car through DEQ - but in the case where my ideal engine tuning does not pass emissions, would it be possible to install a different setting to pass the emissions? (Maybe I should email Volkswagen's executives, huh?)
Anyways, tell me more about this Megasquirt system if you would! I am assuming it is a standalone kit, correct? I'd be surprised if they made a plug-in Peugeot 505 kit. Assuming it is a standalone kit, it would probably contain basic instructions on how to configure all of the sensors and whatnot? At this point I don't know squat about my engine, but I am a quick study and will make sure to obtain a proper shop manual to look through. The prospect of +20% fuel economy is very tempting and a power boost, as I have been looking back longingly at my 404's 1.6L that gets 30 mpg and has a similar power/weight ratio.
Thanks again for sharing your knowledge, it is hard to come by information like this!
Wade
 
G'day Wade.
You would probably find the following website helpful: L-jetronic Fuel Injection Technical Troubleshooting Article
Whilst the layout is different, the GT6 uses the same LU2 setup as your 505.
In the first instance I would urge replacement of both the fuel and air filters.
On my own 505 I fabricated an air intake snorkel system of plastic piping from the front grille to the air filter box which allows cooler air to be inducted. Power output increased noticeably.
I also use 98 octane fuel, with an extra 2 degrees of ignition advance [12 total]. This too has increased power output and better MPG -- even though the fuel costs more.
32 PSI tyre pressures also lessens rollng resistance.

Pavel
 
Thank you, Pavel! I will be sure to swap the fuel filter and air filter immediately (why not? they're the cheapest parts, might as well start with them) and then look into rigging up a cold air intake system.
That website is extremely helpful! Very informative and troubleshooting oriented. I will report back this saturday when I pick up the vehicle.
 
Hi wade,
As your engine is the ZDJL it runs a timing belt instead of a chain as in the XC6,XN1 engine family, first thing I would do timing belt and relative seals (camshaft,crankshaft,auxillary shaft) and then check/adjust valve clearances. This would set up your engine correctly for finer tuning and possibly save the situation of a broken timing belt. Happy motoring, Jim
 
Hey Jim, thanks for the advice. The engine was recently rebuilt by the former owner, it has basically only recently been broken in. It has a new timing belt, and I will chat with the previous owner tonight to find out the condition of everything else. It is my impression that the entire engine was fully rebuilt (top end and bottom end), although I guess it would be wise to check the valve clearances and make sure things haven't drifted since the rebuild. The only thing that wasn't rebuilt and gone through was the fuel injection system, that's why it is my prime suspect.
 
wadehilts said:
Hi Rob,
Anyways, tell me more about this Megasquirt system if you would!
Click to expand...
Megasquirt is one of many ECU options -- probably the ultimate for DIY types. You can solder it up from parts (which I've done twice) or buy them pre-built. I'm using the MS2 to run both injection and ignition. Originally used the standard firmware, but have been running the MS2/Extra firmware for the last few years. That firmware opens up quite a few options -- coil over plug, wasted spark, sequential injection -- that I'm not using, but might if I were starting from scratch. Anyhow, I won't go into the details of mine here, but I'll give you a reading list:

Megasquirt EFI - Fuel injection and Ignition Control ECU MS Extra manuals and forums
http://www.megamanual.com Original manuals
MegaSquirt | Engine Management System | Electronic Fuel Injection - DIYAutoTune.com Where I bought mine

Finally, searching around this forum for Megasquirt should give you a bit of reading matter. I know I posted some info on my own conversion, though that might have been pre-crash (a lot of the forum's history was lost).

Happy to give more details, but you probably should familiarise yourself with the car as-is first and try to get the L-Jet going as well as you can. Maybe that'll be good enough.

Have fun,

Rob.
 
Alright Rob, I'm back - and with a fair bit of reading under my belt on the Megasquirt.
I've started with the wiring and sensors, as that seems to be the most logical first step. I've plan to do the following as far as sensor upgrading use:
  • I don't need to worry about hooking up IAC stepper motor or solenoid because my Bosch LU2 has a handy "Auxiliary Air Device" that will handle cold idle for me.
  • Temperature sensors seem straightforward, I can use OEM or Aftermarket so long as MSII is calibrated correctly
  • I plan on using an Aftermarket Wideband O2 sensor so I can get better air/fuel ratio tuning. I'd imagine this will take some adjustment on the software side of things.
  • I will fit a potentiometer Throttle Position Sensor - seems straightforward.
Here's the big question: Ignition triggering. I know MSII supports the Bosch 0 227 100 124 ignition module, but my 505 (probably) has the Bosch 0 227 100 123.. Are these two interchangeable? Or will I need to wire off of the coil to make my ignition triggering work? the Bosch 123 isn't listed on MSII's page about the 124 Bosch 0 227 100 124 Ignition Control with MegaSquirt-II
I figure once I have this question answered, I will be ready to install the system and begin tuning via computer.
Thoughts? What was your experience here?
Thanks so much,
Wade
 
Hi Wade, I can't say specifically about the two Bosch ignition controllers but generally have "mixed and matched" these before in quite a casual fashion and not had issues. Like everyone else, I've been let down when pushing them hard with dried up heatsink compound or a poor earth. A separate eyelet to the earth screw is good practice.
 
Hi guys, I found some more information regarding the Bosch 123 and 124 ICMs:
http://www.pim-engineering.com/tiedostot/ignitionmodules.pdf
It looks like the 123 is an inductive trigger and the 124 uses the Hall effect..
The pin wiring is shown on the 2nd page. It's close enough that I can see why they would be interchangeable, but perhaps grounding is a little iffy? The inductive trigger seems to require two pins (+/-) and a shielded wire ground, whereas the Hall sensor only has a signal wire and a ground. Also the 124 is supposed to have a module ground on pin 2 which the 123 doesn't have.
MS is primarily concerned with pin 5 which is the positive signal coming from the Hall/inductive sensor.
I'll have to look into this more and report back!
 
The BIM 027 (0 227 100 124) can be ECU driven, as per my Peugeot 605.
The BIM 123 (0 227 100 123) can be ECU driven, as per my Peugeot 405.

I have run the 405's module in the 605 for thousands of kilometres without problems, then back to the "proper" one without a problem. I suspect there is a lot of tolerance built in to these units.
 
Yes, it sounds like the inductive and Hall sensors produce similar enough square wave output signals that they can be used interchangeably? In this wiring diagram: Bosch 0 227 100 124 Ignition Control with MegaSquirt-II it just looks like megasquirt is taking in the square wave signal directly from the distributor and using it to determine crankshaft position. Given your experience, it sounds like the signal is similar and the grounding/shielding is comparable as well - or else you would have had plenty of issues!
 
Hi Wade. Sounds like you've been busy.

I agree with Addo. I've been running the 123 without problems. I have a feeling that the dwell timing might be better honoured with a digital trigger, but the 123 gets the timing right.

On your other points:

Yep, no need for IAC. The Bosch warmup stuff works fine.

I'm using the standard Bosch coolant temp. sensor. For air temperature I replaced the AFM with some stainless pipe and stuck a Ford thermistor in there. Had some heat soak problems so moved the thermistor to behind the bumper.

I'm using Innovate LC-1 for WB. Works fine for me, but MS2/Extra supports many WB controllers, and plenty of people seem to complain about the LC-1.

Hyundai (Excel I think) TP sensor fitted the spindle and only needed a simple flat adaptor plate.

Wiring up the sensors first is sensible enough, but you're kind of stuck with a big-bang implementation. You might consider doing fuel-only to begin with, but my experience with the 604 was that I had noise issues on the tach input which only surfaced when I brought the ignition in. This negated most of the tuning I'd done on fuel-only.

What tach-input are you going to use? Toothed wheel is optimal, but I'm still getting by on a locked up distributor with the vacuum advance plate locked to full advance. I've timed the reluctor pulse to happen just before the maximum advance, making for pretty accurate ignition timing -- even during cranking. Don't be tempted to try with an ordinary distrubutor. The mechanical advance will mess everything up.

Have fun,

Rob.
 
Hi Robs,
I will follow you lead on the LC series (I guess the LC-1 has been replaced by the new LC-2)! Thanks for the tip. I've learned a lot this last week, the number of tabs open in my browser is approaching the resolution limit on my computer screen!
For the tachymetric input, I was thinking of using the MSII V3.0's ability to control the coil directly. I've read up on this, and it appears that since the Bosch 123 uses an inductive (VR) sensor, I should investigate controlling my timing with MSII's built-in ICM.
This would essentially involve wiring my VR sensor directly to the MSII - where a VR circuit will convert the signal into a square wave - and then connecting MSII to the coil to control dwell.
I got most of that info on: Distributor Pickups

"In general, the most suitable option for controlling ignition timing advance on a distributor with a VR sensor on MegaSquirt-II is using the VR sensor circuit built into the V3 main board (see step #51 and #52 here) and the high current ignition driver circuit on the V3 main board to control the coil. With the V2.2 main board, you can use a GM 7 or 8-pin HEI module to convert the signal AND control the coil. There is much more on this on the GM HEI page."

I believe this will involve more tuning on the computer side unfortunately.
 
OoOooOO, I just got the part in the manuals you provided about locking up the distributor. I have a lot more reading to do!
 
Hi Robs,
Okay, after a lot of reading and scratching my head, I think I will go for the missing tooth crank wheel tach-input. I figure it would be about as much work as locking up the distributor and using the Bosch 123 module. This seems to be the biggest hardware hurdle I am facing.
Assuming, I rig up the missing tooth crank wheel and all the sensors mentioned previously, I should be set to install my megasquirt and begin configuring all of these sensors. I see what you mean about the "big bang" approach, where I will have made numerous adjustments before any testing is done. Your concern there is that identifying errors may be difficult?
I plan on re-reading the set-up document, which I just skimmed (I've read the entire hardware manual now), and basing my next move off of the set-up procedure. If I can do a partial implementation without the risk of wasted tuning time, great! If not, I'll plan on setting aside a long weekend to really delving into the entire process. I have other cars (like the trusty old 404) that can take car of me in the downtime!
 
Hi Wade,

I was a little confused when you responded to my question about tach input with an answer about coil output, but it sounds like you understand that OK. So your input could come from the dizzy reluctor, or, as you now favour, toothed wheel (good choice). Output has to get to the coil somehow -- through the BIP373 that comes with the MS, or the 123/124 Bosch module. I favoured the external trigger because I didn't like the thought of 7A or so going down the harness to be grounded by the MS -- seemed like a recipe for noise (I'm no electronics expert though). With the 604 I went another way again. Put the BIP373 that came with the MS in its own case with heat sink and current limiting resistor and mounted that in the engine bay. Pretty much a DIY 124 Bosch module.

Yeah, the "big bang" will see you trying to start the car without knowing whether or not it's sparking or squirting or whatever. Having done it all at once, it's more work narrowing down what problem(s) you have. Going toothed wheel might make fuel-only more viable as a first step. Adding in spark later would only involve wiring changes and blocking off vacuum advance.

Some other things that you'd need to plan for up front are wasted spark/coil over plug and sequential injection. These are all supported by the MS2/Extra code, but they do involve changes to the hardware assembly and adding a cam sensor. Given my time over, I still don't think I'd bother with the spark changes; sequential injection has more appeal, but it's pretty good without that too.

Incidentally, you can skip the MS stuff about the fuel pump relay and fuses. The 505's tachymetric relay deals with all that for you. Still worth having fuses on the power feeds though.

Have fun,

Rob.
 
robs said:
Some other things that you'd need to plan for up front are wasted spark/coil over plug and sequential injection. These are all supported by the MS2/Extra code, but they do involve changes to the hardware assembly and adding a cam sensor. Given my time over, I still don't think I'd bother with the spark changes; sequential injection has more appeal, but it's pretty good without that too.

Rob.
Click to expand...

I thought I'd throw my 2 bobs worth in here as I spent a while messing with EFI on the renault version of this motor.

The 'nicest' engine was the one controlled with Renix injection. that was sequential spark via a dumb dizzy, and batch fire injection.
I never got the car to run any better than it did with that set up.
Started first crank, idled smoothly, was economic, never spluttered coughed or did anything unusual. Considering it came out in '85-ish, the factory did an incredible job. My only gripe was the fuel cut on over run happened right on the threshold of my most traveled speed limits, so at times made it feel my car had the throttle control of a chinese taxi driver.

I went to sequential injection, and wasted spark running 4 coils via an autronic ECU. Granted, this system allowed me to tune transients like fuel cut on over run etc, and to experiment with cams and E85, but all up, i'd be bullshiting if I said there was an improvement over the Renix system.
Once i added cams and lightened flywheel etc, the motor gained grunt but lost all of its niceness anyway so comparisons become a little useless.

From the little I know about the pug engine control, if I ever ran the same motor( and I have thought about a 505gti) the first thing I'd do is get rid of the antiquated ignition, then look at the fuel.
If there is a difference in performance/feel between sequential and batch fire fuel injection I don't know what it is.
For my money (experience) it is academic.
I could move the sequential injection anywhere through the cycle and bugger me if I could feel a noticeable, let alone profound difference.
It was set where the book said to set it, but that was the only academic (again).

Jo
 
Hi Jo.

Sequential injection isn't meant to make any difference to power. Like you say, run it 180° out and there's no performance loss. But it has been tested to show that the idle is more stable. This makes some sense since pulse widths at idle are pretty short and will be lengthened if you're only squirting one injector at a time rather than two. I find I need an AFR of ~13.5 at idle and this might have bother with emissions tests for rego -- if we had such a thing. I know they do test cars in the U.S. at least in some towns.

Mind you, I haven't been enthusiastic enough about it to rejig the current set up, and reading what you say saps my enthusiasm some more.

The Renault set-up was obviously streets ahead of the Peugeot, but I think the distributor isn't the biggest culprit. Mr Bosch built it, but he built the injection too. I'd say they're equally antiquated. The Megasquirted Pug is much more economical and responsive and I don't think it's just the dizzy.

Have fun,

Rob.
 
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