Page 1 of 1

Engine problem

Posted: Thu Mar 01, 2007 8:39 am
by Disco-Blue
Hey guys

When my engine is hot it sometimes it appears to missfire. I am going to check the plugs but I also think that it could be the coil or leads. Has anybody else had this issue before

Its a 3.5L V8

Posted: Fri Mar 02, 2007 5:55 pm
by gumboot412
I had much the same problem and yup, replaced plugs and leads, although the removed ones all looked fine, having done it ran sweet again. Mines the 3.5 as well.

Posted: Fri Mar 02, 2007 7:42 pm
by Disco-Blue
Cheers man will start on that this weekend. Whats a set of leads for one of these worth?

Posted: Fri Mar 02, 2007 11:24 pm
by Cloggy_NZ
One thing I have learned with Land Rovers is that if the left front wheel is wobbly it is probably the right rear wheel bearing that needs adjusting.
Make sure you know what the problem is before spending money on spare parts you might not need. But the ignition and sparkplugs can cause some strange symptoms in these things.
Case in point is my mates Disco, also a 3.5 EFI. One day out of the blue after parking it in the garage overnight the damn thing will start but not run. As soon as you let go of the key the engine stops. Seems like it was flooding, strong smell of fuel etc. Checked for spark which there was plenty of but we knew it had both spark and fuel otherwise it wouldn't have started at all. We tried everything, swapped computers, distributors etc. All without luck. Could not get the engine running normally. After several days of trying (over a period of several weeks) the decision was made to let the experts look at it and the Disco was towed to a mates garage.
First thing they did was replace the spark plugs. Problem fixed.
Never expected something so simple to create that much of a problem. Would have also expected the engine to run even if half the sparkplugs were stuffed. You think it would have developed symptoms like misfiring before deciding to stop running all together. But no. It just stopped one day when it felt like it.
My suggestion after our experience is to start with the plugs and work backwards from there.

Posted: Sun Mar 04, 2007 5:20 pm
by Disco-Blue
Thanks I will give that a go.

Posted: Wed Mar 14, 2007 8:04 pm
by Fish13
How did you get on Disco-Blue? Plugs fix the problem?

Posted: Thu Mar 15, 2007 7:45 am
by Disco-Blue
Nah spent $50 on new plugs and still playing up, I am going for new leads I think. might also look into a new coil as well just to make sure she keeps a nice strong spark.

Posted: Thu Mar 15, 2007 8:42 am
by Steve_t647
Hey next time it is playing up pull a plug lead and move through them all until you find the one that is funny.

Swap that lead with one that seemed OK and see if the fault moved with the lead or not.

Should help track it down. Good luck

Ditto

Posted: Fri Oct 05, 2007 5:35 pm
by RSA-Disco
Hi Guys
I have a similiar problom,only mins starts and idles perfectly but wont go above 3000 rpm.Replaced fuel pump,checked for air leaks etc. Any help out there?
Thanx

Re: Ditto

Posted: Fri Oct 05, 2007 7:06 pm
by Cloggy_NZ
RSA-Disco wrote:Hi Guys
I have a similiar problom,only mins starts and idles perfectly but wont go above 3000 rpm.Replaced fuel pump,checked for air leaks etc. Any help out there?
Thanx

Hello and welcome to these forums. You will find us a friendly bunch and these pages are an awesome resource for information.

You say it won't go above 3000rpm.
Do you mean it starts missing and farting once the engine reaches about 3000rpm or does it flatly refuse to go above 3000rpm but it doesn't misbehave at all until that point is reached?
If is doesn't misbehave but refuses to go above a certain rpm, one item which springs to mind is the throttle potentio meter. This is an easy item to check with a multimeter.
With the ignition on but engine not running the volt meter should read between 0.33 and 0.35 volts when connecting to the red and green wires on the throttle pot.
You can find this sort of information here:
http://www.rpiv8.com/carbs-2.htm
The RPI engineering website is a very good resource on Rover V8 engines. That is all they do.
I have a manual which goes through the process of checking the whole fuel injection system for faults using a multimeter and tapping of the plug on the engine management computer. Can email this as a PDF to you if interested. You will need to wait till Monday though before I can do this.

Posted: Sat Oct 06, 2007 12:56 pm
by Hunter
hi mate have you checked out your relays for the ecu .i brought a 86rangie 3.5 efi of trademe the guys who owned it before me spent lots trying to work out a similar problem ..so they sold it as they had replace coil plugs leads dizzy cap, fuel pump every thing part the computer(ecu) so they sold it as ecu was over $1000 and they werent sure if they brought 1 it was the problem with it .relay was the fault with it.. make sure earths a good and leads are put on right.sound silly but if u not got leads right the will cause misfire as they cross over the wrong leads (hotwire unit puts out a lot off power)differences between early rover v8 lead lay out is different to hotwire efi v8 layout..hope u get it going