Just this afternoon I saw that white with red stripe wire after reassembling the instrument panel and took it back down to make sure I did not overlook it. I could not see where or what it was for so I folded in back into the dash. Well thanks to you I now know what it is and for what. Thanks again for Volvo forum.

 

How do you know if your 2115 chip is broken? I just hooked up the red/white wire, drove it around and theeen, realized that I fried it. I have the old sensor from the other cluster, will this work if I install it?

What causes the speedometer / Odometer to go bad?

 

Hooking up the red/white wire to the double spade on the instrument cluster is the surest way to fry the 2115 chip. When I did it, we didn't start the car (just turned the key to the II position). We realized something was wrong but it still fried the driver on the taxi output of the 2115 chip. That basically knocked out the signal to the cruise control and to the ECU.

If you start the engine and run the car, it will fry the entire chip. The red/white wire comes from the coil and can have large voltage spikes that wreaks havoc with digital electronics. When the entire chip is knocked out, you lose both the speedometer and odometer not to mention cruise control, etc.

I can't really come up with a good test to verify the 2115 chip is bad. But assuming that it all worked fine before you hooked up the tach wire, odds are your chip is toast.

Good luck

 

My experiences square with act1292's comments. I did drive it around when I fried my chip. And it was completely gone. How to test... well, there is a method... I found this over on cleanflametrap.com, or rather darkdelta pointed it out to me on another thread. Electronic Speedometer Notes
I never followed these instructions, as I had neither an ociliscope nor a wave form generator at my disposal. But his notes are quite complete, and I have no reason to doubt them. Still, as act1292 points out, if you have hooked it up, it is almost certainly done with.
On a side note, if you are digging that far into the speedo, you should consider replacing the gear that frequently fails at the same time. I didn't, only to have to replace it 2 months later.
As to replacing the chip itself, if you are reasonably comfortable with a soldering Iron and can get your hands on a solder sucker, it is not that difficult to replace, although I would not recommend it for a first timer. But if you do replace the chip yourself, try not to heat up the chip more than needed, as that will do your chip no favors.

As to your old chip--was the speedo working in the old cluster working, or were both the speedo and odometer broken? If the speedo worked, but the odometer didn't, it was probably the drive gear, and the chip is fine. If both the speedo and odometer are not working, then it is likely the chip.

 

I got my hands on some nice center hubcaps for the steel wheels of the Snake. Or rather, after a little bit of work on a polishing wheel, they look quite nice.
I rather like the center hubcaps with black wheels. But they're not really black, just whatever semi black/brownish color that was under the original horrible plastic wheel-covers. So I hope to re-paint them sometime. But that is not in the immediate future.
I also noticed while inspecting my wheels a little closer that the drivers side rear wheel is bent a little. It is very little, but it would account for the ever so slight rhythm I get when I drive. It is very little, (both the rhythm and bend) hence I hadn't noticed it much. But, I figure I'll see if I can fix that when I go to paint it. that will likely not happen until I get new tires. Which may be a while.
Now, I'm kind of on the look out for the chrome wheel rings that go on the outside of these steel wheels. I see some on ebay for $99, but I'm in no hurry. I'll wait a bit and see what else comes my way.


I guess I don't quite follow you here. Do you mean only the headliner that is in the sunroof? In my experience, I didn't need to remove any other part of the headliner to work on every moving part of the sunroof. The gears that drove the sunroof all practically fell into my hands when I took out those screws, and when I pulled the sunroof last time, all I had to do was remove the headliner in much the way you would remove the doorpanels, just five or so fasteners on the front, then it slit back, and I could get to everything I needed to to remove it entirely. Spraying it with silicon lubricant worked nicely.

Of course, as my car is only 20 years old instead of 35, it may be setup rather differently. I tried to look it up in OTP, but that was not as fourth coming as I had hoped.

 

Been busy lately. I do have something to report, though.

I was under the hood, looking around, and noticed (about 2 weeks ago) that the line to the fuel pressure regulator was split badly, and not connected. Shortening it didn't work (it just split further), so I didn't worry about it, and it seemed to be making no difference. I was getting between 23 and 24 MPG.

Next time I went to the junkyard, I saw a 740 with that tube, and took it, and put it on mine. Then I didn't think about it much. But as I filled up over the next couple of weeks, I noticed that my mileage was consistently better--25 to 26 MPG. Then I remembered that I had fixed that hose to the fuel pressure regulator. So, I figure it must have been broken the whole time I've had this car, and that it was doing bad things to my mileage--although not as bad as I would think.

Picture below is the part I am talking about, but NOT my car--too lazy to go take a picture right now.


That is all for now. But I have been enjoying the 26 MPG. What are other people's mileage experiences? I keep wanting to switch it out to a manual tranny, and part of my justification is that it should get better mileage. But what is the real-world of this? Does that square with people's experiences?

 

the vacuum line causes the absolute fuel pressure to be lower when there's a high vacuum. figure 35psi or so with the throttle closed, and 44psi with the throttle wide open.

so without that hose, you'll be at 42-44 psi all the time, which means the engine will be using a little more fuel. the O2 sensor will partially compensate (as it will detect this as too rich, and lean things out some).

 

It's been a while since I've been on the Forums, and boy are there a lot of new questions. Reading over them, they are getting answered by people who know far much than I do. I was about to say something... and then noticed the next post already covered that. Also, I've been working on my mother's 2005 XC70, and the people in that part of the forum are not very useful...

A few things I've been noticing, and wanted to get some second opinions on. I got this working in the summer, and had little call to use the heat. Now as it is cooling off, I like heat in the mornings. The only problem is that it feels like the heater has two positions: Blazing hot and off. Yes, I can move it all the way across the warm/cool spectrum, but that doesn't seem to make any difference at all. Is this the usual behavior for a 240 heater? I realize these are Swedish cars, but I figure even over there, once the car heats up, you want to turn back the heat a bit... Searches on the forum gave me bucket-loads of info on how to replace the heater motor... but I got not so many details on how or if the heater feels like it is either on or off but now in between...

Second, the fuel pump (or so I presume) sounds awfully noisy. I didn't notice it at first as usually I am inside the car when it is running anymore. But the other day, I started it, and got out, and as I walked by the passenger door, I thought it (or something else located in that quarter of the car) seemed rather obnoxious. I see that these pumps seem to fail rather often... is being noisy often a symptom of that? Or should I just not worry about it?

I'm also going to see if I can figure out how to use the OBD on my 240. Lots of people talk about getting codes from it, but all I see is a probe, 6 slots and a red light... and I'm not sure how that translates into a code... I will search around the internet a bit more, but thus far, I've not figured it out.

 

answered my own question on that last one...
http://www.matthewsvolvosite.com/for...hp?f=2&t=24944

I am getting a 2-3-2 code... Hum... in socket 2.

 

on our 87 240, at least, the heater control works a wire that directly pushes the heater valve on the engine side of the firewall.. I know on the last couple years, they changed the AC controls around a fair amount to be more like 940, I dunno if 91 is one of those years. on my 92 740, the heater control water valve is on a servo

re: OBD codes, this is my goto for them http://www.swedishbricks.net/700900F...ne-Codes1.html

2-3-2 is a nice vague one, you'd think they'd toss seperate codes for rich and lean. can be almost anything from a worn O2 sensor, air leaks in the exhaust manifold confusing the sensor, high (or low) fuel pressure as mentioned, leaking vacuum hoses, etc etc.

 

I'll be looking through the OTP guides I have & see if they reveal anything about the heater core. But I guess it is safe to say that it should not be behaving that way.

As to the OBD code, I just reset it (Thank pierce for the link--it was clearer than other instructions I found). When I drive home from work today, I'll see if the code reappears. My guess is it was a residual code from when the fuel pressure regulator was not properly connected. At any rate, I'll probably know this evening.

 

Link relevant to my heater valve question:

http://www.matthewsvolvosite.com/for...hp?f=2&t=20386

It would seem that the heater valve is the problem. It appears from the discussion here that the valve automatically opens and closes to keep the heater core at the tempeture you've selected. And it would appear that that functionality is not working on mine. Why would it still be able to turn it off? I'm guessing at the far end of the heat/cool range, it manually pulls the valve all the way closed. So... I'll see about getting a new heater valve...

In way of clarification, the OTP seems to indicate that 87 through 91 models use the same system, and 92-93 use the 740 style system. So it would appear that my valve should use the same system as is in pierce's.

 

that automatic open/close functionality you describe sounds like ECC, the climate control on the 760/960 models, and not the manual system found on lower end models.

pop the hood, look at it. the heater valve is pretty obvious on the lines between the block end the firewall, and if someone moves the temp selector lever back and forth, you should be able to see the cable move. my 240 is never home any more (teenager daughter at her senior year of HS), but I have a pic handy that shows the vacuum actuated one on a 1991 940SE(960 with ECC climate control)



and ... oops, its not visible in any of the 1992 745T engine pics I took a couple weeks ago.

 

Long time, no post. Sorry. Been busy as the Christmas retail season is coming up, and I need to be ready for it.

Under the hood seems to look like what you have above... picture to come... but this is what I found in OTP:

It seems like what they are showing is inside the car... right behind the vacuum control bubble thingys. I will see if I can get it apart, and show you what i've discovered.

 

My discoveries appear to square with OTP.

Below is the location where the wire goes from my heat control lever.


It is hard to see, so here is a better close up.


So, I think I have to replace this part for the heater to work properly.

I took a picture of the area where the hoses form the heater come through the firewall and go into the engine, but the depth of field was too shallow on the picture for it to be worth anything.

 

Well, it has been sometime since I've posted anything. Working in retail, the Christmas season is a pretty busy one. But things have slowed down a bit. Although, I don't anticipate doing much work the Snake until mid Jan, I can post some updates to where I am at this point.

Everything, as far as the heater goes, still stands as I last posted it. I did get my hands on another heater control valve, however, I have not had time to put it in. The real game-stopper is that I will have to get the fan out to replace the capillary action device that somehow controls the temperature. Alternatively, I can just get the Volvo solution that doesn't include the capillary action thermometer device.

I got a new antenna mast and motor, and I have installed them. When I got the car, it had some aftermarket radio that you manually pull up and down. But, now I have the factory style antenna that goes up and down. That makes me happy.

I have the gauges all lit up--it took some time time to find the bulb for the mini-tach, but now they all work. Of course, they're all a little on the dim side, but such is life.

I replaced the sun-visor clips. Ordered the parts from FCP Euro. Easy-peasy. I also got the new antenna mast at that time and new motor and transmission mounts. The Motor mounts are very wobbly, and need to be replaced. I figure I will at the next oil change. that seems to be the recommended time.

I got some front bumper trim, so my car doesn't look quite so junky from the front anymore. I also worked on and fixed up the air-dam a bit on the front. It was hanging down at an odd angle, but when I put the trim on, I managed to correct most of that.

Finally, for Christmas, i got a nice powder-coated set of Virgo rims. I've got great brothers. I am figuring out what I want to do with tires. My current tires are not in need or replacement, but I have been thinking I may get new tires for my Virgos, and get a set of snow tires for the steels. I could use some snow tires, as it has been to this point a snowy winter in WV. So, I'll have to research and figure out tire sizes. I know that the Sedan and Wagon used different size tires... but that is about the extent of my knowledge. I'd like tires that do well enough in the rain--the 240 sedan seems to slide quite freely on slick roads. But part of that may be that my old tires are not that great at shedding water. On Titan Joe's 740, we ran Goodyear Triple treads, and they were amazing in the rain. I have some Goodyears on my 240... but not triple-treads. So, I'll be working on that.

Pictures later on.

 

This is a useful graphic for helping me understand how tires are rated....



Actually the rest of the page, Finding The Right Tire Size For Your Car - Future Tire, is also pretty useful.

My car currently calls for 185/70 r14. That is what is on it right now.
What I am finding for an 85 turbo is 195/60 r15. I'm thinking something like that is what I need.

 

a lot of older less common tire sizes are getting really hard to find.

before getting creative and trying to substitute non-standard sizes for a given application, make sure that load factor is equal or not much more than a little greater than the original tires for the car. a tire with too low of a load factor is unsafe, and a tire with too high of a load factor will ride and handle like crap.

 

With regards to your heater control valve, I would just replace it with a cable controlled valve and not deal with climate controlled type. I recently installed the following on my '90 240:

Cable Operated Heater Control Valve - Heater Valves & Cables

I had move the location of the valve slightly and needed a longer control cable. A visit to my local Home Depot and I purchased a generic lawn mower throttle cable. It did the trick and it seems to work rather well. Not climate controlled but has good temp control.

 

I've found a fair number of the 195/60 R15 on tirerack.com. I'd rather buy local, so I will talk around and see what the local tire shops can do for me. Pirelli has some P4 tires with a high tread rating for a decent price that I am considering... but I really don't know. We've had Goodyear triple-treads on the 740, and they worked great. But my criterion is to get as good a treadware rating for my dollar. I have considered getting these tires, as well as a pair of snow tires to mount on my steels. Any thoughts on that? Or are snow tires largely obsolete with these all-weather tires?

As for the heater control valve, I may do as act1292 suggests. You link is useful. at FCP Euro, they wanted something in the rage of $50+ for the volvo oem replacement valve... and it was not a climate controlled modle. that seemed a bit much. At $25, I am much more willing to consider.