Maybe start with an ignition upgrade?

[dnp]

I've got a 95 D90 ST that's really begun to run rough. It idles fine, but when accelerating, it starts to bog down (unless I mat the skinny pedal, at which time it runs "better" but still feels weak) Within the last 18 months or so, the PO replaced the total exhaust (including cat conv), plugs, fuel pressure regulator, fuel filter, air filter, and replaced the ECU with a "rebuilt" unit. Obviously, the problem is most likely electrical or fuel delivery, but I'm not sure where to start........my first thought is to make sure I'm getting PLENTY of spark. Accordingly, my first question is: does anyone recommend changing out the ignition system like an MSD distributor, coil, CD box, etc..? It seems to me that this would help a lot of D90 woes, including starting issues (Let me add that this is my firsy foray into Land Rovers. Heretofore, I've owned Jeeps, Land Cruisers and Blazers, but I've always thought the D90's were the coolest 4x4's out there.....now, if I can just get this thing to run correctly!

[Tim Scully]

I havent changed mine yet but as soon as it starts to give me problems Im probably going to change it out for the MSD dizzy. There are several good threads that have information on different systems. If you use the search function to look for MSD ignition it gives you a bunch. Here is one of the threads. Good luck and let us know how it comes out

http://www.d-90.com/forum/showthread.php?t=8650&highlight=MSD+ignition

Cheers,

Tim

[MonLand]

I've got a 95 D90 ST that's really begun to run rough. It idles fine, but when accelerating, it starts to bog down (unless I mat the skinny pedal, at which time it runs "better" but still feels weak)

Lack of air? Do you have a clean air filter?
Lack of fuel? Is your fuel filter recent?

[dnp]

Lack of air? Do you have a clean air filter?
Lack of fuel? Is your fuel filter recent?Yes on both counts. It sure feels like fuel delivery to me, but since so much has already been replaced, I thought I might want to start with a completely "fresh"/updated ignition

[chris snell]

Have you tried running a can of BG 44K through it?

[MonLand]

Yes on both counts. It sure feels like fuel delivery to me, but since so much has already been replaced, I thought I might want to start with a completely "fresh"/updated ignition
I never heard of the _need_ to go with an upgraded distributor (I understand it can be nice to have one, but it is never needed). Make sure you get a spark (that's easy, just take a spark out and verify that you see one). Make sure your ignition wires are good (It was recommended to me to replace those every year or two on a daily driver; running the truck at night in a moist environment will be a good test). Make sure your distributor cap is not broken. Make sure the distributor rotor cap (is that the proper name?) is good. Make sure your coil is good.

Here is my take on your problem: replacing the ignition might introduce additional problem without you knowing about it. As a result you might be searching for two problems at once.... not easy.
Fix your current problem, then install upgrades.

[TXRover]

Mine did that intermittently, mostly under load. The lead plugged into the coil was not secure, I only noticed it because I was trying to decipher the problem at night. Sometimes, it is that simple.


Joseph

[andyrad]

I have had a small problem on occasion when my battery dies. For the next couple days after I get it started it runs rough through the 2000 rpm range until it charges up. Maybe look at your battery. The electrics on these things are shit.

[jimngo]

There could some other possibilities, in my order of probability from highest to lowest:

* Throttle position sensor is faulty
* Vacuum advance not working
* Ignition amplifier module faulty
* Fuel tank breather clogged
* Air or Fuel filter clogged (I see you already checked that)
* MAF is dirty or faulty
* Air leak after MAF
* Crumbling catalytic converter is clogging the exhaust
* Mechanical advance on dist. not working
* O2 sensors
* ECU is faulty

[dnp]

Well, I got tired messing with this problem, so I took it into a local 4x4 shop that's had some experience with Defenders. First thing the guy told me was my distributor's shot. Based on what I'm quickly learning about these trucks, when it comes to electrical items, I want to upgrade from OEM.

After reading through a multitude of past threads, I'm pretty confused on what the "setup" is for an aftermarket distributor. Some say Mallory some say MSD some say stick with stock. Likewise, I've read a lot of general comments, but I haven't seen many specifics. That being said, can anyone advise me on what they've found (hopefully from personal experience) to be a really good upgrade for a worn out distributor? If possible, please also post part numbers (If I can replace mine with successful results, I'd like to post a full write up on what might be a solution for others with similar issues)

Thanks for any help.

[Monkeyboy]

I'd be curious to know what's "shot" before replacing the whole distributor.

My '94 Disco has 143k miles on the same distributor that's in your '95 ... ok, I think the ignition amplifier module is in a different place on the Disco ...

I have replaced the advance module, and like most folks here will encourage you to be sure that you've got new LR cap and rotor installed.

Cheap as I am, a new cap, rotor, wires, plugs, amplifier, vacuum module would go a long way to improving driveability.

KAA

[dnp]

I'd be curious to know what's "shot" before replacing the whole distributor.

My '94 Disco has 143k miles on the same distributor that's in your '95 ... ok, I think the ignition amplifier module is in a different place on the Disco ...

I have replaced the advance module, and like most folks here will encourage you to be sure that you've got new LR cap and rotor installed.

Cheap as I am, a new cap, rotor, wires, plugs, amplifier, vacuum module would go a long way to improving driveability.

KAAKeith, thanks for the comments.

My mechanic told me that the rotor shaft is moving up and down too far / has way too much slack in it and that when it's running, the distributor is causing a knocking (I had heard that sound before, but I didn't know the dist. was causing it) Being as how I'm somewhat new to Rovers, I was thinking that anytime one can remove the Lucas components from these vehicles, the better of one would be.....is that an incorrect belief? Also, my main objective is to end up with a better ignition system than what I'd be replacing / rebuilding.....Irrespective of the cost difference, is the Mallory the wrong way to go or is the expense the concern? Thanks.

[Monkeyboy]

My mechanic told me that the rotor shaft is moving up and down too far .

Hmm, sounds like someone might have puled up on the old rotor and broken the plastic retaining clip for the shaft :(

If you can still find a dist repair kit ... crap, can't find the part number ... it will have all the bits you need. The last one that I bought, that sits on the shelf in my garage, was someting like $35 ... but if you're not up to the task yourself, the MSD / Mallory replacement might be just as efficient.

Don't let the mechanic just keep your old distributor!! Stick it in a box and send it to me :)


Irrespective of the cost difference, is the Mallory the wrong way to go or is the expense the concern? Thanks.

I have no experience with either MSD or Mallory in the Rover application ... just a cheap bastard here :)

KAA

[Neil McCauley]

Yeah the Rover distributor can be a real PITA if the rotor is stuck on the shaft when you try to change it. A simple tune-up can turn into a entire distributor overhaul. I try to remember that nowadays by having some kind of tool like a flat head screwdriver to hold the pick up down while I pull off the rotor. You can rebiuld the distributor, its not that hard, you can even see how the parts go together if you piece them together with the springs. It would take a lot of time and miles to wear down your distributor (Series Vehicle age) and I doubt yours is that bad unless it was installed wrong or was already faulty to begin with. It's probably loose because your mechanic pulled on the rotor too hard. Good Luck.

Neil

[Monkeyboy]

HeHeHe, I wasn't going to assign blame to anyone, but Neil's probably right.

I cut a small groove in each side of the old rotor with the Dremel and just break it off the shaft. With my luck anything I used to hold down the reluctor would slip off and break something else!

A teeny bit of dielectric grease under the new rotor will make it come off easier the next time you have to change it too.

[MonLand]

HeHeHe, I wasn't going to assign blame to anyone, but Neil's probably right.

I cut a small groove in each side of the old rotor with the Dremel and just break it off the shaft. With my luck anything I used to hold down the reluctor would slip off and break something else!

A teeny bit of dielectric grease under the new rotor will make it come off easier the next time you have to change it too.

Now that I read this..... I fear for mine. I did have to pull hard to get the rotor out. Not sure if that broke anything (truck seems to run fine).... Gonna have to check this soon....

[Neil McCauley]

Now that I read this..... I fear for mine. I did have to pull hard to get the rotor out. Not sure if that broke anything (truck seems to run fine).... Gonna have to check this soon....
It's not going to break anything but if you pull it out too far like what me and Keith are talking about, what happens is the tiny springs inside pop off and the entire shaft comes off the oil pump shaft (which is a pain to re-align without taking the distributor off) So you'll have to pull the dist. and put back together the entire assembly. If its old, its a good time to check your vacuum advance mech and diaphram are working properly as well and it can't hurt to install a new ignition module with di-electric grease (It'll look like toothpaste on the old one)

Neil

[jimngo]

I agree with Neil and the other folks that you probably don't need a new distributor. The mechanical advance may not be working properly and you just need an overhaul of the distributor. And as Neil says, you might as well check or replace the vacuum advance and the ignition module. By the way, I have an ignition module relocation kit for sale if you want to go that route.

[Neil McCauley]

Jim, how much were you asking for your relocation kit and does it come with a new module?

Neil

[Monkeyboy]

The dizzy rebuld kit that I have in the garage says RTC5971 on it in case anybody needs the p/n.

[jimngo]

Neil, I sent you a PM.