Rolls-Royce and Bentley Forums banner

1 - 10 of 10 Posts

·
Registered
Joined
·
4 Posts
Discussion Starter #1
Hi! So I purchased a '94 bentley brooklands and proceeded to drive it 300 miles home (not the brightest idea as it had been sitting for some time) and now the engine has developed a shake. Seems to only do it on the lower revs and goes away with higher speeds. I have a video of it here: video

I changed the spark plugs but still no luck. I'm not sure what it could be, if anyone can tell from this video or has any ideas I should try please let me know! Thanks
 

·
Registered
Joined
·
34 Posts
A quick armchair (meaning uninformed) diagnosis would be a misfire in one or more cylinders. That would be consistent with a shake at idle but less obvious at higher revs. Do you remember if any of the plugs you took out showed any different residue? That might be a suggestion of a misfire, and in which cylinder. In addition to plugs you may need to replace the leads or even the distributor cap. Of course, there could be a bunch of other causes but I'd start there.
 

·
Registered
Joined
·
4 Posts
Discussion Starter #3
A quick armchair (meaning uninformed) diagnosis would be a misfire in one or more cylinders. That would be consistent with a shake at idle but less obvious at higher revs. Do you remember if any of the plugs you took out showed any different residue? That might be a suggestion of a misfire, and in which cylinder. In addition to plugs you may need to replace the leads or even the distributor cap. Of course, there could be a bunch of other causes but I'd start there.
I think some of the plugs had some oil residue on them that seemed like it shouldn't be there, I will look into replacing those thanks for the suggestions!
 

·
Registered
Joined
·
50 Posts
If it ran smooth initially but no longer after 300 mls it's also possible that the fuel system got clogged somewhere from residue or old fuel.

After the checking of air filter, plugs, wires and cap I'd empty the reservoir, change the fuel filter, add injector cleaner, fill up with expensive fuel and drive for another 300 miles.

Good luck & let us know the outcome!
 

·
Registered
Joined
·
162 Posts
Those cars are looking great but very often were not used for months or even years. Before do any serious diagnostics take a look at this forum for topics and tips about standard works with newly bought cars - especially cleaning electric connectors and fuses.

Edit: Do not forget to tank the car full ;)
(anyway check for fuel leakages, just to be sure)
 

·
Registered
Joined
·
4 Posts
Discussion Starter #6
I'm going to order the stuff now and do everything you all suggested. Do any of you know which HT leads & distributor cap I should order? Its hard to tell which ones will work
 

·
Registered
Joined
·
151 Posts
Your car has the Zytec engine management system. No distributor cap.
You should use the specified NGK spark plugs and no other brand. Install with no anti-seize and torque to 20 lbf ft.

Before spending $650.00 on HT leads I would remove the spark plugs and inspect the coloration and perform a compression test.

A dark plug will indicate HT lead/ignition coil issue, a white spark plug will indicate an issue with the fuel injector(s).

Part #s:
--> Part catalogue page (part number search) (bentleymotors.com) <--
 

·
Registered
Joined
·
4 Posts
Discussion Starter #8
Your car has the Zytec engine management system. No distributor cap.
You should use the specified NGK spark plugs and no other brand. Install with no anti-seize and torque to 20 lbf ft.

Before spending $650.00 on HT leads I would remove the spark plugs and inspect the coloration and perform a compression test.

A dark plug will indicate HT lead/ignition coil issue, a white spark plug will indicate an issue with the fuel injector(s).

Part #s:
--> Part catalogue page (part number search) (bentleymotors.com) <--
Sadly I threw the old spark plugs out after replacing them. Would I be able to tell by removing the new spark plugs and inspecting them?
 

·
Registered
Joined
·
428 Posts
The car has to be fully warmed up and driven for at least 20 miles, more is better.
Don't leave the car to warm up in the drive way, the faster it warms up the better, and that's done by driving it right away.
Be gentle in you driving however until the engine is hot.

The sooner the engine warms up, the sooner the computer will stop enrichening the mixture and the more accurate the reading will be on the spark plugs.
 
1 - 10 of 10 Posts
Top