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jkincel 05-26-2007 01:19 PM

Loosing power at 1000 RPM's won't accelerate
I have recently swapped out my distributor, timed, and replaced distributor cap and rotor. 98 4.0 6cyl turns over right away, and idles perfect. The problem is when I start driving I loose any acceleration past 1000 RPM's, tried shifting into 2nd gear and same thing... anyone?

jkincel 05-26-2007 01:20 PM

I have re-timed everything exactly the way it should and double and triple checked everything, reset the distributor, brand new cap and rotor, new plugs and wires. this last time it accelerated fine but a little past 2000 RPM it made a poping noise and became slugish, and now wont accelerate past 1000RPM's again. I have been at this for 3 days with the resolve of one problem leading to the next... please any advice is appreciated

Odhinn 05-26-2007 01:22 PM

Is it idleing rough?

jkincel 05-26-2007 01:27 PM

it is idleling perfectly smooth

Odhinn 05-26-2007 01:33 PM

Your timing chain could have jumped a tooth, or the pop could have damaged one of your sensors. Hard to say without seeing it. Someone here may have personal experience with something similar.

Wish I could help further.

Scotty355 05-26-2007 02:59 PM

Did it act like this before you replaced everything?
Is this the reason you swapped out the distributer?

Scotty355 05-26-2007 03:02 PM

It could also be that your catalytic converter is blocked solid, too much restiction as the rpms go up.

Just thinking out loud, without seeing it..

foxinthemudd 05-26-2007 04:03 PM

I agree with scotty. I've had similar problems in other rigs I've owned. I'd be driving along then there would be a point where I couldn't go any faster and start decreasing in speed. check the cat.

jkincel 05-26-2007 05:21 PM

I have just got back from testing the fuel pressure, it was fine at 48 PSI. I think that it is the catalytic converter aswell from all the misfires with the timing and distributor. I know a welder, do you think I could salvage one and weld it to my existing setup, or is it better to have a shop take care of it and get a new one?

jkincel 05-26-2007 05:25 PM


Originally Posted by Scotty355 (Post 85730)
Did it act like this before you replaced everything?
Is this the reason you swapped out the distributer?

It always seemed like it was loosing power and wasnt very fuel efficient but I thought it was just normal, it had a rough idle before but once I accelerated it would smooth out. A shop told be that it was probably a bad injector but, I believe that it was the distributor now... I have had the car for 10,000 mi now and it is at 150,000 the check engine light has been on since I got it from a shady dealer ignorance on my part, but I have enjoyed working on it.

I replaced the distributer because the shaft was loose and moved back and forth burning up my cap and destroying the rotor.

skeeter 05-26-2007 05:39 PM

Fuel filter, air filter, clogged fuel lines.

BTW, how do you time a 98?

jkincel 05-26-2007 06:59 PM


Originally Posted by skeeter (Post 85762)
Fuel filter, air filter, clogged fuel lines.

BTW, how do you time a 98?

Air Filter is brand new and the fuel filter shouldnt be replaced unless you suspect fuel contamination but, the fuel pressure is solid...

To Time a 98 4.0 inline 6

1. Turn the crankshaft with a large socket attached to the balancer hub bolt threded to the front of the vibration dampener wheel.

2. Locate top dead center (TDC), highest point the piston reaches, of piston 1

a. remove spark plug #1 insert a length of wood or plastic (not metal) into the spark plug socket.

b. start cranking the hub bolt while watching the wood. You want the wood to rise out of the spark plug socket, indicating the piston rising. Make sure the wood doesnt become pinched or lodged inside.

c. Next find the notch located on the inside lip of the vibration dampener

d. get a flashlight and a rag, just behind the vibration dampener at about 1 o'clock you will find timing marks (you will need a flashlight to see even in broad daylight) 8|||4|||0| align notch to zero, this is TDC for piston 1.

3. next remove distributor cap and see that the rotor is pointing at the #1 piston for the fireing order, if it is not you will need to adjust the distributor until rotor points at 1 (look on the distributor cap for a 1 indicating the #1 piston)

crack a beer your done

be careful timing yourself for the first time this is how I caused my problems with the catalytic converter. You dont want your enginge starting and misfireing too many times it is hard on the engine and can lead to other issues.

hope this is helpful please respond with any tips or suggestions to these instructions.

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