I have a 1990 240 and a 1989 740 and would like to know which oil and gas additives are best for restoring compression and cleaning injectors. Both vehicles have over 100k miles and i of course want to keep them running as well and as cheaply as possible.

RSVP

ScottSC

No chemical additive will "restore compression". Just over 100K miles is absolutely nothing to a Volvo 4. What is your mileage? Why are you worried about compression?

NOTHING will clean REALLY dirty injectors IN THE CAR. The best is removal and ultrasonic/bench cleaning. Amsoil PI does pretty darn good for slightly dirty injectors in the car.

If I change my oil & filter every 3 months & use the Mann filter & Quaker State 10-40 & 10-30 without using oil additives that are crap any way,Whats the worst that can happen?Forget about oil additives.They are a waste of money at best & can do more harm(PTFE/Teflon) at worst.A good oil has all the additives you need.BTW,I like to use Techron or duralube Feul injector cleaner

I HAVE TRIED ALOT OF ADDITIVES IN MY CARS (RISLONE, MOTOR-UP, RESTORE, STP, BARDHAL, ETC.) I AGREE THAT THEY ARE NOT REALLY NECESSARY AND DO NOT OFER MUCH INMPROVEMENT USUALLY. HOWEVER MOTOR-UP ACTUALLY HELPED MY 240 TURBO RUN SMOOTHER AND COOLER. (I NOTICED A SIGNIFICANT IMPROVEMENT) THIS IS IN NO WAY AN ENDORSEMENT FOR THE PRODUCT, IT REALLY DOES WORK!!!

JUNIOR BAPTISE

Second Steve's comments about oil additives. In over 24 years of using and selling AMSOIL, I have yet to see any legitimate documentation showing that any of the oil additives do as claimed.

The best fuel additives I know of are made by AMSOIL (PI) and BG (44K).

Redline makes a good one, and Techron is very good. Most of the others aren't as effective, though they may be less expensive by the bottle.

Forget about oil additives: none of them are worth anything, and some of them (especially the PTFE mixtures) do positive harm. You will not be able to "restore compression" with an additive. Use a good motor oil at the correct weight and you'll be set. Best of all, use Mobil 1 synthetic (either 5-30 or 10-30), Valvoline synthetic, Amsoil or Redline.

Good gasoline additives, used occasionally, will clean the injection system very well. Recommended by Brickboard users: Techron, Amsoil, BG-44, Valvoline Synpower, and STP in the silver bottle. The Amsoil and BG are only available from those dealers and are a little pricey. Techron may be had at Walmart and works wonders.

Don't forget to use a good gasoline as well. I usually use Amoco (midwest brand) which keeps everything clean and costs about 7 cents per gallon more. Every time my kid fills up with Kum & Go (convenience store) gas, the idle drops, the tailpipe smells of sulfur, and the car seems to clog up.

I found that regular use of quality gasoline (Chevron 92 or Texaco 92) and an occasional bottle of fuel injector cleaner keeps the engine running smooth. I do whatever possible to avoid the cheapo gasoline, unless im out in the middle of nowhere and there is no other option.

No additive of any kind has every passed my Volvos' lips. I second Steve suggestoin about gasoline. I stick with Amoco exclusively. Run about 3-4 tankfuls of their premium through it and the injectors will be clean. While I follow th premium recommendatons for my 960, my wife alternates premium with regular in her '86 244 GL, especially when the price differential isn't too great. MAybe 3-4 tanks regular, to 2 tanks premium.