Rough Idle an flashing MIL

2121 Views 4 Replies 4 Participants Last post by dryjoint, Jun 4, 2012

sujole

Discussion Starter · Jun 4, 2012

Hi

I have just bought a 1999 3.0 S-Type and would just like some confirmation of the main problem.

The car starts fine but has a rough idle. When driving, if hard acceleration is used, the MIL starts flashing, reducing the throttle opening makes the light go off. The light does not flash at idle. I have checked for codes but there are none stored. I have also checked while the light is flashing but, again, no codes. I suspect that this is caused by the air leak under the manifold. Can anyone confirm?

Also, when moving, there is a sort of scraping noise coming from the nearside rear wheel. The bearing has been checked and found to be ok. Any ideas?

Save

1 - 5 of 5 Posts

57jam89

· #2 · Jun 4, 2012

Hi

Rough idle can be caused by the air leak at the rear of the inlet manifold.
If your engine light is on then there must be codes!

Save

leaping cat

· #3 · Jun 4, 2012

Flashing MIL means the catalytic converter is in danger due to excess fuel usually caused by misfire.

Save

sujole

Discussion Starter · #4 · Jun 4, 2012

57jam89 said:
Hi

Rough idle can be caused by the air leak at the rear of the inlet manifold.
If your engine light is on then there must be codes!

I have moved some of the pipes at the back of the manifold while the engine was running which seemed to smooth the idle out which is why I suspect the normal problem. The light only flashes for a short while but I have checked for codes while it is flashing and also with the engine off but nothing shows up.

Save

dryjoint

· #5 · Jun 4, 2012

Sounds like a coil pack is starting to go , just had the same thing myself. Last weekend it eventually threw up a code on cylinder 3, of course it is one of the 3 under the manifold. Got the ( 3 under the manifold)coil packs and 6 x plugs changed car now runs and accelerates a lot smoother with an increase of about 4-5 mpg. I know I should have changed all six but I now have 5 'good' coil packs that can be changed relatively easily?

Save

1 - 5 of 5 Posts

This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.

Top Contributors this Month