Out of forum but I hope you wont mind because basically is a mechanical question...

While I was servicing my 100 a good friend of mine let me borrow a 1987 Volvo 740 Wagon which is a very reliable and strong cruiser and I have a lot of respect for.

The car was in very good mechanical shape in spite of her 200k miles...

SO I drove it for a couple of weeks and a few days ago it began to happen that ocasionally I will press the gas and nothing will happen as if the gas was not getting there but it will go away.

So I thought it may have dirty injectors and I pour a can of injectors cleaner with the gas and it seemed that the problems was fixed... but later this same afternoon tha car wouldn't crank at all and now I can start the engine but it will only stay on if I keep pumping the gas and keep it over 2000 revs... I was able to move it to the back yard driving with the two feet to keep the revs up. The timing belt is due but it can't be that because I can move the car and keep it on.

My ideas are to check and clean the injectors and to check and clean the throttle body...

Is there any sugestions you may have?

Thanks and sorry to be out of brand but is not worth to sign in into a new forum just for this temporary situation...

First I would change the fuel filter. If that didn't solve the problem, I would look towards the fuel pump or see if there was a secondary filter in the tank.(Not sure if volco uses one or not. In the audi this filter is integrated in the pump. When you pull the fuel filter, you should be able to tell if you have pressure if not the problem is the pump. By checking it this way you will be able to tell if the problem is before or after the filter. i.e if the problem is injector (after the filter) or if it is pump related (before the filter)
Good Luck

You'd never figure out the solution to our lil' ignition switch bug on a Volvo forum! :-D

-Jeff

<ul><li><a href="http://www.brickboard.com/FAQ/700-900/">http://www.brickboard.com/FAQ/700-900/</a</li></ul>

And this one...

much more specific...<ul><li><a href="http://www.brickboard.com/FAQ/700-900/EnginePerformanceSymptoms.htm">http://www.brickboard.com/FAQ/700-900/EnginePerformanceSymptoms.htm</a</li></ul>

Hard to say, as the fact it doesn't rev isn't much information to go on. However you need timed spark, compresed air, and metered fuel for an engine to run. Which of these is missing when you try to start it?

<ul><li><a href="http://apps.volvocars.us/ownersdocs/1985/1985_740_GL_GLE_Turbo/85740_08.htm">http://apps.volvocars.us/ownersdocs/1985/1985_740_GL_GLE_Turbo/85740_08.htm</a</li></ul>

After a mechanic replaced two fuel pumps and couldn't get it to idle, I brought my VW mechanic by and he said it was the AMM by listening to it try to idle. I found someone parting out one near by and got the wagon going the next day. The write ups should work in that forum for your trouble shooting.

The plastic insulation for all the wiring in the engine's wiring harness was defective from the factory and this causes all sorts of driveability issues.

Take a look on the insulation on wire that goes to the oil pressure sender down by the alternator, and the wires for the coolant temp sensors in under the intake runners, and then back at the big multi wire plug-in on the firewall. You'll probably find all the insulation is crumbling off and the wiring is bare. If it is, the harness in the engine compartment needs replaced. $400ish and 4hrs of time.

Couple things you can try.
1)Unplug the vacuum line from the back of the fuel rail mounted fuel pressure regulator and see if fuel comes out. If it does, you know the regulator has failed internally.
2)Unplug the wiring harness from the MAF and see if the car runs the same (Limp Home Mode) if it does, you know the MAF has failed
3)Remove an inspect the plastic accordian duct that goes from the MAF up to the throttle body. These love to crack, creating HUGE air leaks and the car will run as you describe.
4)Check the breather hoses that plumb into the plastic duct, especially the one that goes down to the vent fitting on the block. These love to rot from oil, and that fitting in the block loves to get clogged, build up pressure and pop out, giving you a huge vacuum leak.