okay a while back posted about driveabilty issues with my daughters 93 240....on take off or when idling, when you give it gas it has a slight to very noticeable hesatation, if you move the pedal down slow sometimes it doesn't respond til 1/4 pedal, doesn't do it everytime but does have a miss, runs fine when driving at speed....cleaned MAF sensor and throttle body (very dirty t/b) worked well for a bit, then the engine light came on, said MAF sensor...thinking maybe the harness wasn't plugged in well, reinstalled and cleared code...but then I got heated 02 sensor code....but the MAF was gone, huh? Okay so I told the daughter it was okay to drive til I can look at it again, well then it started idleing up and down 200 to 300 rpm at idle...I ran a can of Lubromoly through the tank thinking it could use a good clean....well today I still have the 02 sensor code and now it's added injector code....should I change the 02 sensor and check for the dirty injector or...thoughts...shoot it
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well I didn't shoot it, but I drove it tonight, drives fine really...when you come to a stop it seems...fine, but the minute you put it in PARK it starts the erractic idle..up and down and up and down?

 

how far are you willing to go in regards to restoring this Volvo? how much money are you comforortable spending? you willing to do the work yourself? in my opinion this sounds like a 1000.00 dollar fix. I don't say that as if it's actually a gross amount. To bring the Volvo up to what some call 'Stage-zero' you are going to need to do some reconditioning work. after which the Volvo will of course reflect the reliability it is renown for.

For stage zero, which is another term for "tune-up", except more dynamic; I would suggest you first take care of the vacuum lines, make sure they are all new replaced or in excellant condidtion.

If you have not done so, replace the O2 sensor. i know it's pricey, but it's a matter of whether or not you are actually going to be keeping this Volvo.

There is a thermostat valve in the airbox, make sure this has not failed, replace this too.

The positive crankcase ventilation (PCV)system is very important to keep in good condidtion, once attended too it usually is good to be left alone for a while, so take care of it. replace the
PCV hoses, breather box, flame trap, and o-ring for the breather box. this will require you get into some tight places. look directly under the intake manifold, it's a black box or resevoir.

Make sure you replace all main v-belts.

If you are unsure of the condidtion of the timing belt, get this replaced and attend to the proper timing. dont forget to replace the timing belt tensioner if/when you so this. FYI, if doing this I suggest you replace the front engine seals while your at it.

Drain and flush the coolant system, then properly bleed it. easy-squeezy.

look at the radiator hoses, replace these if necessary...FYI, Volvo OEM you may be looking at 300 tops +/- cost to replace all. not bad for years of reliabilty.

with the coolant system replace the thermostat

Take the intake manifolf off and replace the injector seals, sounds big but i assure you it's simple. The o-ring kits are very cheap...FYI, the plastic spacer that comes withthe kitdoes not actually fit the injector, use the old one. with the intake manifold off replace the gasket.

replace the fuel filter.

Clean the electrical connectors with electrical component cleaner, usually alcohol and acetone mixture.

the last item i'll posit is the fuel sending system. be sure of the functionality of the main fuel pump and in-tank fuel pump, these may need replacement. though can be pricey. An easy item to make sure to replace is the fuel pump relay, take care of this.

these items are to start off...once taken care of I would not doubt you'll see an imporvment in the Volvo.

good luck.

 

okay tonight after my ride home (very nice drive too no problems) I was told look at the idle valve, and make sure it's clear and checked with 12v and valve closes nicely...reinstalled, and then the problems the daughter told me about started....When I started it up, it idled real high, say 1200 rpms....when you gave it gas it idled down to say 500, then would die...restart and do it again....sometimes it would idle high, but mostly die out?

 

well, in regards to what you speak of...

have you inspected all the air conduits, or hoses, that go to thw throttle body and idle-air valve? one or two may be disconnected at a certain point. also, make sure you understand the dynamics of a component called the throttle switch, makw sure this is adjusted properly. is your air filter clean? make sure nothing is blocking air going to the manifold.

 

well I broke down and took it to the shop yesterday....it needed a MAF sensor, and idle motor (both good used) and an O2 sensor...they also cleaned and adjusted the throttle body...there hourly rate was a bit high but they were fair on parts....but it sure runs sweet...it saved the bullet

 

Glad it is running good now.

 

i'm thinking the repair cost was near 400, for parts...tke care of that Volvo.

 

Read this post, Im in a similar situation, am at a loss to figure it out. 1993 240 2.4lh, new....feed pump, main pump, fuel tank, have replaced IAC,MAF, ECT, speed sensor, air intake hose, plugs,cap, rotor, exhaust system including cat. Starts up, idles fine,runs down the road until for some reason, looses acceleration. On a flat, up a hill, full tank, 1/2 tank. Paly with the throttle long enough clears up and runs down the road until it does it again. No rhyme, no reason......took it to a shop, ran fine for him for 3 weeks....

it won't stay broken long enough to do any testing, as soon as I get it home.......no longer has the problem.

open to suggestions, already ruled out C4.....won't let me have any :-(

 

So, what led you to using the "parts cannon"? The problem with this approach is that you never concentrated on the problem by correctly diagnosing it. How do you now know if all the parts you threw at the problem are correct, not defective, and correctly installed? Many Asian parts today are simply bad, like sensors, etc. This now is very hard to diagnose--it sounds like one of those parts you replaced is not up to the job. Something electronic is glitching now and then. Any OBD codes?

 

Give it a wiggle test...with the engine running go through the engine bay wiggling all the different wiring connectors. If you notice a change in the idle while wiggling something you've possibly found the problem.




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while you're 'wiggling' don't forget to wiggle the crank sensor wire...