Is Everything Worth Changing?

[maneesh]

92 model 164k. This is what I am planning to replace in order to alleviate my problems.

Poor fuel economy on motorway (normal around town). Replacing all plugs and leads. Plugs were replaced 5 years ago.

Vibration felt in brake pedal when hard braking (no, different from ABS pulsating). Replace front discs and pads.

Poor ride and handling. Replace all 4 shocks. Current shocks last replaced 60 or 70k ago.

Even after buying the parts through LOC 15% discount, it's still going to be a big bill.

The only item I've never heard of anyone changing on their 400 is the ignition leads. I'm doing it because someone recommended changing them at 100k. What do you think?

Thanks in advance.

[Loz]

I think that you might take the £2k that you are gonna spend and use your car as a part ex for a 94 model and save yourself time and hassle?

Ps. if its anything like the IS and GS it won't have ignition leads it will have coil packs...

SOrry if this is a bit negative but thats a lot of work when you could just find a car thats in better shape. I would also want to be sure that the proposed changes would rectify the problems. fuel economy for example? I'd have thought an LPG kit would be a better solution...

JUst one guy talking...

[Fidgits]

Nope.. I was thinking the same as Loz... your probably better off investing in a newer LS.. trade yours in against one a couple of years younger, they hold their value quite well, so it shouldnt cost you too much..

[maneesh]

Cheers for the advice. Let's say my car is worth 3k, and I plan to spend a grand on these bits and pieces. That means I have 4 grand towards a newer LS400. If I was gonna buy a newer one, I'd opt for a Mark 4 or newer, which is way out of budget. Plus, I know the history of my car, and so much has been changed (steering rack, water pump, power steering pump, EGR pipe, gearbox speed sensor, front springs, front anti-roll bar).

So, by spending 1k now, I see myself being able to postpone a purchase of a newer one for a year or two, whilst I get the cash.

Alternatively, I could dump the 400 and get a Mondeo. Yuk, no way!!!

I think I will not bother with the leads.

[lexuslexus]

you are right about LS400 plug leads, they are a problem. There are two conventional coils - one for each bank of cylinders. The plug leads are the thin type and are prone to shorting between each other. Your local Lexus dealer can plug in their wonderful machine and tell you if you have any probs. and if so which cylinder ( this might be free if you ask nicely) . They also part company at the plug end. You can inspect them yourself - the nearside is easier, the off side you have to remove some of the induction air pipes to get access. Take care pulling the lead off the plug, they can be tight. Look for signs of shorting along the lead - usually whitish marks - you can wrap plastic insulating tape at this point simply to increase the distance apart. You can check each lead yourself with a simple multimeter set to resistance. The resistance of each lead should be appropriate to its length. A full set of leads before discount is around £252 plus VAT - how do they justify this? Similar leads can be found on certaing Jananese cars eg Micra bubble. ( about £5 ) It is strange that you are experiencing higher fuel consumption at motorway speeds - I presume you have the overdrive switched on? Does the overdrive switch work ie can you feel it change up? Have a good think about a Mk3 I bought a good one, one owner FLSH for £4900. Good luck.

[maneesh]

Thanks for the tip on checking the leads. Will have a look tomorrow. Yes, overdrive is on, and it changes to 4th.

It's weird, I still get normal stop start consumption of around 17-20 mpg. However, on cruise at 65, I only get 22 tops. Now, just last year I went from Bristol to London at 70mph on cruise and I got 32 mpg! Even once, I drove at 120mph on cruise from the Midlands and got 19mpg. I think that the plugs must be seriously fouled after 5 years of London driving. Will let you all know if plugs really do make a difference.

P.S Leads at 252+VAT? With 15% discount, I have been quoted 129+VAT. Even retail price isn't close to 252. Are they gold plated???

[ColinBarber]

If the plug leads are that expensive it might be worth importing them from the US. If are are going to change the leads you may also want to change the distributor cap?

I would have thought that if your plugs are so bad that they make that much different to economy that you would feel the engine isn't running that smooth.

Have you checked your air filter or that your brakes aren't binding?