Thread: My first post - Ignition Troubles

Hi Everyone, I've got a 1987 3.5 EFI Range Rover Classic. I bought it cheap after the previous owner had an LPG fire under the bonnet. I've since repaired, roadworthied and registered it and have put a few thousand K's on it. After sorting out other noises and rattles (wheel bearings etc) the last problem I need to solve to make it run tip-top is the ignition. So I'll start with the problems, solutions and symptoms as I progress.

First of all, after about 1,000km, at anything about 80km/h (part throttle, cruising) the engine started to leap around in the engine bay, it felt like it was trying to leap out of the truck and do the bolt. It was making the whole car shake, it was unbearable. I am pretty certain that the EFI is all in tact, the Lucas 2AM AFM had been opened by previous owners, so I grabbed my exhaust gas analyzer and reset the spring tension and start position of the armature attached to the flap. Exhaust gasses are fine. Cold starting is still a pain in the arse and I have to let it warm up for 5 mins every morning before taking the kids to school. (I've checked the CTS multiple times and I sincerely don't believe it's the culprit)

So next I went to the spark. Previously the spark had been set correctly at 6deg adv by the RAVE manual, first time I've ever had to buy a timing light LOL. It DID have a good strong spark on all cylinders, but after the engine tried to escape on the highway I re-checked the timing and there was either no pulse, or a very irratic pulse from cylinders 1, 3, 5 and 7. New plugs, leads, dizzy cap and a replacement coil saw a good strong pulse return to all cylinders, but the engine still tries to escape on the highway. I should mention that I am unsure which distributor came with the truck, but it is connected to a bosch module on the passenger side fender near the coil. Did I mention that it runs FINE at anything below 80km/h?

Next I checked the advance, I even disconnected it at one point, this only made matters worse and yes I followed the RAVE and set the timing with the vac advance connected.

The only joy I've had has been to set the timing by ear, which ends up with LOADS of advance, the timing strobe is showing something like 24deg advance at idle, it runs fine, starts fine, and the violent shaking at highway speeds has been reduced to a mildly annoying rattle, like an unbalanced tire.

After all is said and done, with all the extra advance, the engine is firing like a champ, loads of power, kicking up and down better than ever before, but it seems to me like this is wayyyy too much advance, especially considering the rattle is still there at highway speeds. But if I put any more advance on it, it starts to run rough as guts, so I set it as far as I could before it started dying then bumped it back a bit to smooth it off.

I did read in another post that if the wires from the dizzy to the bosch module are arse-about then it'll put your timing out, so that's the next thing I'm going to check in about 5 mins, while I get some photo's to accompany my post. I look forward to reading theories, but I don't look forward to someone telling me the timing chain has slipped a tooth LOL

Cheers.

P.S Pic's coming soon.

Hi guys, I've been real busy lately, about to explain why. The fix for the engine trying to escape was simple, in principal.

Basically, on at least two pistons, the top rings were broken. One was broken in 3 places. The number 5 piston was a different story. It would appear that someone, somewhere down the line had dropped a small bolt down the manifold.The top of the piston looked like rice bubbles as did the head, luckily I was able to chip the remnants of the small bolt off the head and remove the ring from the piston, it had pretty much fused the ring to the piston. So cleaned all that up, put the engine back together and it started first go. So glad to have it running smoothly again.

There's another major problem now but it deserves a post of it's own.