I bought a 1991 Volvo 740 Non-Turbo Sedan. And recently I have been noticing that the acceleration in horrible. It's a four cylinder by the way, but still. When I am at a light, and I push the gas ALL the way to the floor...is takes about 4 or 5 seconds to acutally accelerate. And when I was trying to check the carb, I saw that oil somehow had gotten in to there a long time ago, but I don't know. So what can I do about the acceleration and the cleaning of oil off of my carb?
Thanks!
2007-09-28 10:24:52 · 9 answers · asked by Anonymous in Cars & Transportation ➔ Car Makes ➔ Volvo
Try to manually shift the car from first gear on take off and see if the acceleration is any better, if so the shift down cable me be broken or off of the throttle causing no down shift on take off.
The air filter could be clogged and or the intake hose from the air box to the throttle body could be collapsing and not allowing the air to flow properly giving you no bottom end power.
Does the engine light come on or is it always on, you can manually check for codes if so.
2007-09-28 11:55:47 · answer #1 · answered by Anonymous · 0⤊ 0⤋
Volvo 740 1991
2016-12-15 03:48:52 · answer #2 · answered by ? 4 · 0⤊ 0⤋
i've had the same issue on my 1990 &1992 740's. things to check first are the air hose from the air filter box. if it has a hole in it, it needs replaced. while there check the air filter for replacement also.
next, check the flame trap. it is volvo's version of a pcv valve. it is located under the intake manifold toward the rear of the engine. it has an approximately 1" hose attached to. if this is clogged it will force oil into the throttle body causing it to get gummed up and can cause poor acceleration.
other things to check would be the spark plugs and wires. there is a greater load on the engine during acceleration and misfiring plugs will usually show up then.
hope this helps and good luck
2007-09-28 14:50:57 · answer #3 · answered by FORK 3 · 0⤊ 0⤋
some really good answers here but note:
1. flame traps are now made of plastic [they still clog]
2. dont let carb cleaner get into the constant idle motor[this can ruin them] take the throttle body off of the car for cleaning[3 nuts a quick disconnect fot the throttle position sensor and 2 vacume hoses and buy or make a new gasket.
3. if tune up related parts are recent and in good shape suspect the air mass unit [bosch system only] try unplugging the air mass unit [forces system into limp home mode] it will run poorly but if performance actually improves replace it [not cheap] and replace the air tempature thermostat in the air cleaner housing at the same time [damper door sticks in the heated air position above 120 degrees F,] ..
4 if renault/bendix system [very similer to jeep 87-93] uses a general motors map sensor instead of air mass unit, check vacume line going to this for airtight connections
5 purchase a robert bently manual and read the chapter on retrieving, interpeting and clearing codes. [personaly i feel that while the haynes manual is very good the bently manuals are more complete ---i have both and consider it money well spent]
2007-09-29 04:13:24 · answer #4 · answered by hobbabob 6 · 0⤊ 0⤋
I can tell you what the problem is but unless your very mechanical you will not be able to fix it.Volvo's do not use a PCV valve there equivelant is a flame trap,this consists of a thin strip of brass wound around to form a restrction for air flow,this is positioned between the intake throttle body and engine crankcase,they get plugged up so the engine cannot breath,you end up with a lot of pressure on the backside of the pistons.You will have to take it to someone who really knows Volvo's.
2007-09-28 14:54:07 · answer #5 · answered by the bear facts 5 · 0⤊ 0⤋
Defective EGR system components, i.e. the EGR valve, EGR solenoid, and/or EGR exhaust passages. IF AFTER... all emissions systems are inspected and no faults found, consideration should be given to the CAT. We can not recommend replacing the CAT before a through diagnosis. The EGR system is prone to collecting carbon build-up. Since the EGR valve pulls exhaust gasses from your exhaust and introduces them back into your engine's intake air over time it will become clogged or stuck open/closed from the carbon deposits. The vacuum leak is causing you to have lean fuel mixture which will cause you to fail the NOx portion of the test. Solving that one is going to be difficult as you will probably have to check each vacuum line. One other thing that could be causing you to fail is a bad cooling system. If the car is running warmer than normal (not hot), it will fail. No way to cheat the test as there are many issues either alone or combined that can be causing your failure.
2016-04-06 05:46:21 · answer #6 · answered by Anonymous · 0⤊ 0⤋
There are some good carb and intake spray cleaners available at your local auto parts store. If this doesn't work the problem may be in the fuel filter. Cost to find out about $3.00.
2007-09-28 10:29:29 · answer #7 · answered by Alanrt1 4 · 0⤊ 0⤋
First of all you don't have a carb on that car - it's fuel injection. I'm not sure what you were looking at that looked like oil was in there. Maybe your air cleaner is extremely dirty. Try replacing the air cleaner.
2007-09-28 12:15:05 · answer #8 · answered by Somethingtotry 6 · 0⤊ 1⤋
You don't have a carb on that car it's injected...... Email me and let me know whats going on. I restore Volvos, Have two 740's att..... Hope I can help
2007-09-28 10:31:39 · answer #9 · answered by Mac 4 · 0⤊ 0⤋