i just bought a 99 ram 1500 laramie with the 5.2 engine. it is starving for gas on takeoff,but as soon as you put the pedal to the floor after moving a little.it finally gets a little more power.o2 sensor,vehicle speed sensor, plugs,wires,dist cap and rotor have been replaced today. yet it seems like it still has a misfire in it. no more codes pop up on it. but it does not have enough power from stand still to take off. if you park on a hill. it just chugs.any answers to this? could really use the help.thanks
no power to move on takeoff on 1999 Dodge Ram 1500
by budmcmillan in Eau Claire, WI on July 03, 2014
2 answers 13 comments
ANSWER by DonziGT230 , July 04, 2014
Is the idle smooth or rough? Check fuel pressure, may be a clogged filter or bad pump. Check the exhaust flow. If it sounds really muted and isn't hot you have a clogged catalytic converter.
COMMENT by budmcmillan , July 04, 2014
it idles real rough.but i believe it is either the coil or the converter. it wont move at all when stopped.but once moving a little the engine builds power and then goes
COMMENT by DonziGT230 , July 04, 2014
Was it already like this before you did the tuneup? If it's misfiring you should get a fault code(S) indicating which cylinders, it may have to run for a bit for the computer to turn on the light.
COMMENT by budmcmillan , July 04, 2014
i bought it that way. just the other day the fault codes were random misfiring, misfire on cylinder 1, cylinder 4 and 6. i replaced the distributor cap,rotor. and o2 sensor for upstream.. all were replaced along with the vehicle speed sensor in the tail housing of the transmission... then today i reset the computer with the scanner. ran it a few more times around town. no more codes are coming up... still lacks power real bad,no power on take off. so i replaced the coil. it now has more power. but still lacks alot of power on takeoff. it will barely move until it's rolling. im going to gut the converter and see if that fixes it now. (i have to hold the gas pedal to the floor to get any movement in gear on a incline.once moving.has good power,but still has a miss.) also tested the fuel pressure. was between 47 and 50 p.s.i. any suggestions? im starting to think it might be the timing chain or maybe worn distributor. also found out today the cam shaft was replaced.could that be the issue.and if so any suggestions on how to fix myself.thanks and happy 4th everybody just finished gutting out the converter,it still lacks power. i am now thinking that it has to be that cam shaft or the timing chain.or maybe they didnt put the distributor in correctly.any thoughts on that at all.thanks
They could have messed up the cam timing or selected the wrong cam, many people think a "race" cam is the way to go and ruin a motor. Have you checked ignition timing?
no on the ignition timing,not for sure how to check it without the timing plate on the harmonic balancer.im more old school.this is electric timing with no adjustments. figured i am going to put it on top dead center on #1 today and see if the rotor is pointing the right way.if not they must have put the distributor in a few teeth off or the cam is the problem i am thinking. other than that i am running out of things to replace. will the throttle position sensor make it not have power on takeoff do you think?
I don't know how to time that off the top of my head, and it's probably controlled by a CPS and not the distributor position but not sure. Even with a CPS fired system distributor position does have to be right anyway to assure the spark is firing when the rotor is aligned with the terminal on the cap, not super precise, visual should work. Get a manual or start googling. The TPS as well as many other sensors could cause issues. Spark, fuel, compression...that's the order to check a problem. You've checked fuel pressure but not fuel quality or injectors, check spark quality and timing, then compression. If all those are good; cam timing, cam type since it's been messed with. You bought a broken truck and have to assume there's been all kinda crazy shit done. The more stuff you alter the harder it'll become to straighten out. Check and test first and only replace or alter stuff that's known to be bad. Never ignore the simple or weird...did someone put some diesel fuel in it? Maybe some water in the tank or other contaminates? Replaced a sensor or something with the wrong part? Loose or dirty wires, water in the computer harness connector?
ya.the tank is in good shape.i ran it dry and filled it a couple times now. it very well could be the throttle position sensor. but i find it hard to believe it is the injectors.it would run rough all the time.it wouldnt make it have no power until it is moving. very well could be connectors,the ecm...tps. but im going to take off the rotor now and line it all up to see whats going on.ill also take out the cam sensor.clean it up and check it out.as far as the cam,i have no idea on what kind of cam would have been put in there,or how to even find out at this point. also the dummy had 20 inch rims on it,so i need to find regular sized tires this week... but i dont think it would make a difference with the tires,it still doesnt have enough power to move the vehicle from stop
20" wheels--YOU NAILED IT! The truck is pissed because it's a truck, not a stupid pimpwagon.
but it still has a miss in it when at idle speed. and it should have a little more power with the pedal to the floor. i am leaning towards the t.p.s. or cam sensor.
Cam sensors generally work or don't, never heard of one sorta working. TPS is possible as is the MAS and MAP. If you disconnect the MAS the computer will ignore it and it should run ok, just not perfect. Not sure if it'll ignore the MAP by disconnecting it. As for injectors, if any are shorted it can make the rest of them not work right.
do you know where those sensors are located on that engine. the mas and map sensors.i can check them to see if they are faulty like you said. also i do hear a vacuume leak somewhere, but cannot locate it. sounds like it is down by the torque converter, dont know of any vacuume lines in that area of the transmission tho, but i am not familiar with newer dodge either.. and thanks for your guy's time i appretiate it
COMMENT by DonziGT230 , July 06, 2014
The transmission may have a vacuum modulator, not sure if that year does. If it does then there will be a vacuum line going to it. I don't know if that motor has a cam or crank position sensor or where they'd be located. A manual will tell you.
COMMENT by budmcmillan , July 06, 2014
well now the exhaust is complete, i can definately hear alot of vacuume leaks. on the engine by the tranny and charcoal box. i am going to fix those today if it quits raining out. more than likely thats the peoblem. being it was so loud before.i couldnt hear anything. i'll keep you posted after i get that done. thankyou for helping donzi. much appretiated.................... update....i fixed the vacuume lines and still hear a hissing sound. so i looked to see where from. it was in the back of the throttle body....huh go figure hey... so i take out the intake air control sensor.(ias) totally shot... so i went to o'reillys and bought a new one for 30.00 after tax. put it in,reset the computer. and bam.got power...... there are still a couple hisses around the vehicle so i am going to finish up those lines and see if it gets rid of the rest of this misfire.but it actually will move over a bump now. glad my dodge power is coming back.lol
ANSWER by Datadude , August 04, 2015
On a 1999 5.2 have terrible vacuum lines. Any 1999 5.2L with oem vacuum lines air certain to be faulty. Thank you for posting all the details of this troubleshoot, experiencing same exact issue, lacking power at 1/2 and above throttle. Sounds throaty, ( air sucking sound ) and lacking get up. Check engine light comes on after hard accel sometimes, then goes away. Regardless, I will put time in on this prob, and to the both of you.....than,s for the patience to troubleshoot, write about it, troubleshot and wrote about it. At times on this posts you never hear the fix.....they got too excited and just rode out, leaving you wonder.....or worse yet, to the shop it goes. Thanks both of you!