Won't Start

[pjwells]

Alright, I'll try to keep this simple. The last several days my Disco II will start right up half the time, and the other half it won't. Until today, the times it wouldn't start right away, I would wait a few minutes and try again and it would start fine. When it doesn't start, it turns and turns like it's trying to start but doesn't fire up. After a few seconds of holding the key in III position the "turning" sound of the engine begins to slow and I let off. I noticed a little corrosion on the positive connector to the battery, cleaned and lubed it, but that hasn't seemed to make a difference. This morning it started fine when I left for work, but now it's time to go home and it won't start. The "turning" sound of the engine has slowed enough that I know I'm beginning to drain the battery. Any suggestions???

[parrie]

Hey pj, I'm having more or less the same issue w/ my 99 DII. My symptoms have progressivly gotten worse...in addition to not starting at all now the green "mode" and "sport" lights are flashing. I've been chasing this for several weeks w/ no concrete answer to the cause other than it could be one of several things...possibilities include bad battery, bad MAF, bad crankshaft position sensor, bad XYZ gear shift switch, low transmision fluid. The one item that continues to come up is the battery and it's condition...most say that the rover ECUs are easily effected by low voltage which can cause all kinds of crazy problems that don't seem to make sense. One forum suggested that anything under 14v while running could cause ECU problems. Another forum suggested installing a battery w/ a minimum 1000cca.

In my case the truck turns fine but won't start, M&S lights are flashing, 3-amigos are lit-up but when I hook-up my brand new shiney code reader there are no codes reported. As I mentioned, I've been chasing this for several weeks...thought I had it nailed down to a bad crankshaft position sensor, installed a new one and no go. My last resort is the XYZ switch but before I do I'm going back to the beginning and start by getting my battery and alternator checked to confirm that they OK. I'm thinking this would be a good place for you to start.I'll post my findings.

[ThePhotographer]

Parrie, unless you have the ABS amigo it won't tell you the ABS codes.

[parrie]

Hey Zack, I've had all 3 amigos since I purchased the truck 2 yrs ago. Since the check engine light did not come on I assumed that the amigos came on when the PO removed the air suspension. Check engine has come on twice in the past 2 years; 1st time an O2 sensor came up and an ABS code come up once recently (i beleive the code was P1509), I cleared the code and it hasn't come back. After I extract my broken key from the ignition I'm going to start back at the beginning and confirm the battery is good, alternator is good and dbl check tranny fluid again. Any other thoughts would be greatly appreciated.

[pjwells]

Thanks Parrie, I'll give those a look. As some added info: I recently replaced the throttle body gaskets, and in the process may have not securely reconnected the Mass Air-Flow sensor so I'll give that a good check. Update soon...

[parrie]

PJ, good news/bad news, finally got mine running yesterday...dbl check your battery. My battery was turning the engine fine and tested at over 12volts but apparently it was low enough to cause the ECU to go haywire. I put a fresh battery in and all is well, M&S lights went out & no check engine light. Unfortunately I developed a new problem...when I accelerate the engine rpms continually increase and will not return to idle when I let of the accelerator. It acts like the throttle body is sticking open but I can see that it is in the idle position. Not sure what the cause is. Do you have this issue?

[pjwells]

Parrie, well, still havent been able to get it started. Glad to hear you've got yours started, bummer with the rpm issue, though. I've never had that problem myself, but I would check into replacing your throttle body potentiometer. It's not cheap, but that's what senses and regulates the throttle. It's very easy to replace, though.
As for my battery, I had a buddy try and jump me off yesterday, but it still wouldn't start, which makes me think it's not the battery. I've never heard of a battery being bad, but still not being able to at least be jumped off. I'm still going to take the battery in to my local parts shop and have them test it, that'll be tomorrow, so I'll be able to let you know how that goes. Fingers crossed that's all it is.
Let me know how it goes, I'll do the same.

[parrie]

Hey PJ, not sure what the heck is going on with mine. Up until now the thing has ran like a dream. Going to tear into the throttlebody this evening.

I've actually had several bad batteries over the years...same thing, couldn't even be jump started. As far as LRs are concerned, from what I understand the low battery voltage causes the ECU go haywire causing the vehicle not to start. I hope a new battery does the trick for you.

[pjwells]

well looks like its not the battery. i bought a new one and still wont start. my buddy thinks it's a fuel issue. i really dont want to replace the pump. you know if a Disco II has a fuel filter? i keep finding sources showing it's inline but i dont think that's right.

[parrie]

The only fuel filter that I am aware of is in the tank, I think the DIs have an in-line. Have you checked the the fuel pump fuse and relay in the under-bonnet fuse box? There are several relays that are interchangable, just check the number on top of the fuel pump relay and swap it with a matching relay. If that doesn't work the next step will be to confirm that you have #1: fire, #2 fuel. Do you have a code scanner? I'm wondering if you may have some codes that could shed some light on the situation.

My saga got a bit better...went back over the throttlebody and confirmed that it was clean and not sticking. Removed/inspected the TPS, all looked fine. Put it all back together & fired it up, perfect idle, hit the gas and it went up to +/-2200rpm but then slowely after about 45seconds the rpms dropped to about 1500 but wouldn't go any lower. I'm leaning toward a bad TPS but a bad IAC is also a possibilty. Guess it's time to open the wallet again...

[bkreutz]

I can't see how a bad TPS would make the idle speed hang up. All the throttle and cruise actions are mechanical as opposed to electrical (at least at the throttle body). Does the idle speed not return if the truck isn't driving? If so, rev the engine up and watch the position of the throttle where the cables attach to the throttle body, if it returns to the idle position but the engine is still idling fast then I would suspect the IAC, to verify that this is the problem, pinch off one of the hoses that goes from the intake pipe to the IAC (they make special pliers but a vice grip and a couple of pieces of wood will work in a pinch (pun intended)). If after pinching off the hose. start the engine and rev it up. If it returns to idle immediately, then the problem lies in the IAC system. Have you cleaned the IAC valve? They can get gummed up.

[parrie]

Hey Gale, from what I understand the TPSs can go bad and cause iratic idles. Upon starting the truck idles fine wether it is in park or in gear...the problem only arrises when I step on the accellerator, it acts as if the throttle is stuck but I confirmed that it is in the fully closed idle position. I like the sounds of your IAC test (and your pun), going to give this a try this afternoon. I'll post the results.

Oh yeah, forgot to mention that someone on a different forum had mentioned a bad idle sensor? Guess I'm not familiar, could this be a possiblity?

[Les Parker]

Parrie,

Have you checked to see if there is a vacuum leak on the inlet manifold? Yes, Rovers Efi's appear to prefer 12.8 to 13.4v for the ECU's.

[bkreutz]

Hey Gale, from what I understand the TPSs can go bad and cause iratic idles. Upon starting the truck idles fine wether it is in park or in gear...the problem only arrises when I step on the accellerator, it acts as if the throttle is stuck but I confirmed that it is in the fully closed idle position. I like the sounds of your IAC test (and your pun), going to give this a try this afternoon. I'll post the results.

Oh yeah, forgot to mention that someone on a different forum had mentioned a bad idle sensor? Guess I'm not familiar, could this be a possiblity?

What the TPS does is sense the throttle position to let the ECU know how much fuel to squirt into the engine from the injectors. the only time I've ever seen a TPS make the idle stick is when it gets stiff and won't allow the throttle plate return to idle. The variation of idle speed to load is controlled by the IAC by bypassing air around the throttle body. Just as a check, take the hose off the throttle body, have somebody operate the accelerator, and verify that the plate is indeed closing completely. This has to be done with the engine not running. This shouldn't be this complicated. the system on this truck is pretty crude compared to the new stuff. (fly by wire throttles, maybe that's why I retired from this business) BTW, I agree with Les about checking for an intake leak, a big enough one could act like the IAC though normally a vacuum leak will cause the idle to be poor, but the IAC may be compensating for that. HMMM, now I'm thinking out loud again.:confused:

[parrie]

Thanks again guys. Last evening I went over everything that I can see and could not find any obvious intake leak. Also confirmed that the plate is closing. I removed the IAC for inspection but not really sure what position valve should be in...the valve itself moves freely however it is not in the closed position (should it be?). I cleaned it up and re-installed but there was no change, starts & idles fine, hit the gas and the rpms rise w/o returning to normal. Gale, I did your air hose squeeze test with the engine stuck on high rpm and sure enough the rpms dropped down to normal idle. If your theory is correct it looks like I need a new IAC wouldn't you say?

PJ, if your still out there, how are you making out getting your started?

[bkreutz]

Sounds like your diagnosis is making progress. Before I would change the IAC I would clean it out with some carb cleaner. Take both rubber hoses off and then squirt the cleaner in from both sides. also make sure there are no damaged wires at the electrical connector for the IAC (like mouse chew marks, don't laugh, seen that more times than you would think, apparently rodents like the taste of wire insulation) If none of this works then my next step would be replacing the IAC. When you pinched off the valve and the symptoms disappeared you confirmed the source of the condition.

Thanks again guys. Last evening I went over everything that I can see and could not find any obvious intake leak. Also confirmed that the plate is closing. I removed the IAC for inspection but not really sure what position valve should be in...the valve itself moves freely however it is not in the closed position (should it be?). I cleaned it up and re-installed but there was no change, starts & idles fine, hit the gas and the rpms rise w/o returning to normal. Gale, I did your air hose squeeze test with the engine stuck on high rpm and sure enough the rpms dropped down to normal idle. If your theory is correct it looks like I need a new IAC wouldn't you say?

PJ, if your still out there, how are you making out getting your started?

[parrie]

Thanks Gale. I would never laugh at mouse chew marks, little rascles are the enemy! Did a complete inspection of the IAC and cleaned it up but no go. Before I spend the +/-$200 on a new one I'm gonna see if I can pick-up a $30 used one of ebay. I'll post the results. Thanks again!

[bkreutz]

I second the idea about used parts. One other thing to test though, try unplugging the IAC and see if the symptoms are still there. Might be something in the ECU (I doubt it but I tend to over test things unless I have a good test part to throw on quickly)

[pjwells]

Parrie, It's been a crazy couple of days here. I still havent had time to really dig into my list of issues to check but I've got a light week so we'll see. One thing that's concerning me, in addition to it not starting, is that my heater and a/c don't work and my sunroofs. These have been an issue for a few months now. When I noticed the a/c not working I tried swapping the relays and fuses but still no go. I ran a direct current to the blower motor and it worked fine. As the blower doesn't work on the highest setting it's not the resistor pack, so I don't really know what else to check with that system. As for the sunroofs, I also swapped out relays for that and it didn't work, inspected the switches and they seemed fine, so my next item to check is the under-bonnet fuse box to make sure there isn't any corrosive damage. I'm at a loss for why all these have happened. I'm really hoping it's not a huge electrical system failure. I'm not the most savvy at checking these issues, but my buddy has been helping me tremendously so I'm learning a lot. Any advise is greatly appreciated.

Could all these issues be related?

[bkreutz]

Parrie, It's been a crazy couple of days here. I still havent had time to really dig into my list of issues to check but I've got a light week so we'll see. One thing that's concerning me, in addition to it not starting, is that my heater and a/c don't work and my sunroofs. These have been an issue for a few months now. When I noticed the a/c not working I tried swapping the relays and fuses but still no go. I ran a direct current to the blower motor and it worked fine. As the blower doesn't work on the highest setting it's not the resistor pack, so I don't really know what else to check with that system. As for the sunroofs, I also swapped out relays for that and it didn't work, inspected the switches and they seemed fine, so my next item to check is the under-bonnet fuse box to make sure there isn't any corrosive damage. I'm at a loss for why all these have happened. I'm really hoping it's not a huge electrical system failure. I'm not the most savvy at checking these issues, but my buddy has been helping me tremendously so I'm learning a lot. Any advise is greatly appreciated.

Could all these issues be related?

It's possible that you could have a leak in the windshield that's getting into the Body Control Unit, the BCU is located to the right of the glovebox and it's a common problem where water gets in there, corrodes connectors and causes all kinds of problems. If you haven't got a factory shop manual, here's a link to a site with a free download of the RAVE manual (factory shop manual, it's what the dealer techs(like I used to be before retirement) use. http://www.landroverresource.com/

[pjwells]

bkreutz, thanks! It was reccommended I check the under-bonnet fuse panel for corrosion, but I didn't know to check for the BCU. I will hopefully have time to check tomorrow and will update.

[parrie]

Hey PJ, not sure how much advise I can give when it comes to the electronics on these beasts. I have heard of the leaky window/door issue affecting the BCU that Gale mentions but I've never actually seen one in the flesh. I'm not sure if this alone would be causing the starting issue but it certainly could be affecting the other items if it has taken on water & corroded. Were you able to get a scanner and check for failure codes?

I'm dead in the water on mine until my IAC valve shows up...fingers crossed.

[pjwells]

Well I just removed the BCU and there's no apparent water damage or corrosion, could the BCU simply fault for no reason?

[pjwells]

BKreutz, I checked the BCU, no corosion or apparent damage that I can see. I checked the fuel pump, and it seems to be working fine (spat fuel everywhere). My buddy thought "what the hell" and swapped a few of the relays around and it started up just fine...until...about an hour later when we tried starting it and it wouldn't start. I have a couple of new relays on order (4-prong yellow) so I'll pop those in for the fuel pump and see. As an aside, my buddy's dad thought to check all the fuses with a tool he has (lights up when it completes the circuit), and two of my fuses in the interior fuse box aren't working, and the new ones we put in aren't either. I wonder if this could mean a fault with the fuse box itself. Also, he checked the multiplug for the blower motor, and with the same tool it didn't light up, so I'm thinking it's not getting juice (my a/c hasn't worked for a while, nor has the sunroofs). I ran a code reader on the computer and it doesn't seem to be compatible with LR's, and none of the local shops have a reader that's compatible. What else can I check? Thanks for your help, and sorry for such a long post.

[bkreutz]

Not all the fuses in the fusebox are powered all the time so that test may not mean anything is actually wrong. Some circuits only power up when the appropriate switch is activated. Generic OBDII code readers will only read the emission codes as required by DOT (so a regular scanner should be able to access things like misfires, 02 sensors, and things like that). The rest of the systems (ABS, SLS, SRS, Climate Control) have proprietary software that require special scanners to access them. Have you looked through the RAVE manual that I gave a link to in an earlier post? There's lots of stuff in there (including wiring diagrams) . Good luck.

[pjwells]

The scanner we used was OBDII, so good to know. I'll look into a better scanner and will check with the dealer, they may be willing to read the codes for me at no charge, they've helped me out with info and advice before. I did look thru the RAVE manual, quite a lengthy read, and it does have great info. It's a little over my head at times, but I'm getting there. It definitely helps. I'm gonna look into the wiring first, trace it all and make sure everything looks ok, as long as I can get it to start I'll be able to get over to the dealer for the codes. Thanks.