When my truck starts up it goes up to about 2000 and then after about 30 seconds it drops to about 750 and then keeps fluttering from 650 to about 850 when stopped in gear. But when in park it seems to idle fine. It isnt my fueling because my gauge is fine, and ive already replaced my plugs and wires. What sholud i do next?
tach surge
- Thread starter syty9933
- Start date
Re: tach flutter
Re: tach flutter
ive done it in the last 2000 miles, should I do it anyways.
Re: tach flutter
ive done it in the last 2000 miles, should I do it anyways.
turbodig
Active member
Re: tach flutter
Re: tach flutter
Is it flutter, or surge?
Surge is up-down-up idle, typically in the range of RPMs you're talking about.
Re: tach flutter
Is it flutter, or surge?
Surge is up-down-up idle, typically in the range of RPMs you're talking about.
cloneman315
Active member
Re: tach flutter
Re: tach flutter
what wires did you put on it?
Re: tach flutter
what wires did you put on it?
cloneman315
Active member
Re: tach surge
could also be that stock dis,they short out inside change it with the autozone one
could also be that stock dis,they short out inside change it with the autozone one
BoostedSUV
Active member
Re: tach surge
Did this start after you installed the AFPR?
Did this start after you installed the AFPR?
Re: tach surge
No the fuel pressure regulator helped alot , and it has had this problem for a while.
Cap and rotor or the whole distributor? and if its the distributor how can i make sure?
No the fuel pressure regulator helped alot , and it has had this problem for a while.
Cap and rotor or the whole distributor? and if its the distributor how can i make sure?
BoostedSUV
Active member
Re: tach surge
A vacuum leak, bad TPS, Bad IAC, bad MAP could all cause an irratic idle. Have you checked the timing? Any Check Engine codes?
A vacuum leak, bad TPS, Bad IAC, bad MAP could all cause an irratic idle. Have you checked the timing? Any Check Engine codes?
Re: tach surge
i just took apart everything from the lower intake up , just to put in new gaskets and to prevent any leaks, I havent done anything else listed though, but i have no engine codes
i just took apart everything from the lower intake up , just to put in new gaskets and to prevent any leaks, I havent done anything else listed though, but i have no engine codes
BoostedSUV
Active member
Re: tach surge
And you this problem prior to changing lower/upper gaskets? I would check the timing if you haven't (but if you had lower intake off you probably did). Go over all the vac lines, check TPS volatge (should be around .5 volts at idle and 4.5 at WOT). You could also spray carb cleaner around the TB and Intake to check for vac leaks...
And you this problem prior to changing lower/upper gaskets? I would check the timing if you haven't (but if you had lower intake off you probably did). Go over all the vac lines, check TPS volatge (should be around .5 volts at idle and 4.5 at WOT). You could also spray carb cleaner around the TB and Intake to check for vac leaks...
Re: tach surge
Sorry ,i mean i took everything off down to the lower intake, i guess ill check for timing, and could bad timing cause knock? i have a small amount of knock at full boost and my fueling is on lock, either way its gotta be ignition related
Sorry ,i mean i took everything off down to the lower intake, i guess ill check for timing, and could bad timing cause knock? i have a small amount of knock at full boost and my fueling is on lock, either way its gotta be ignition related
BoostedSUV
Active member
Re: tach surge
Yes, if your timing is advanced you will get a knock and it will definitely cause Idle issues. Advanced timing would raise the RPM and the IAC will attempt to bring it back. Retarted timing will cause a low idle wich would also cause the IAC to try to adjust the Idle. I would start there... check the timing with the EST wire disconnected and set it at zero (TDC). Do you have datamaster? I would be curious to see what you IAC counts are and if they're steady.
Yes, if your timing is advanced you will get a knock and it will definitely cause Idle issues. Advanced timing would raise the RPM and the IAC will attempt to bring it back. Retarted timing will cause a low idle wich would also cause the IAC to try to adjust the Idle. I would start there... check the timing with the EST wire disconnected and set it at zero (TDC). Do you have datamaster? I would be curious to see what you IAC counts are and if they're steady.
Re: tach surge
Thats seems to make great sense. This may seem basic , but how do you check and set the timing to zero? and i did a datmaster run about a month ago, and im about to do another one, once i have everything tuned and checked.
ill have to find my file
Thats seems to make great sense. This may seem basic , but how do you check and set the timing to zero? and i did a datmaster run about a month ago, and im about to do another one, once i have everything tuned and checked.
ill have to find my file
BoostedSUV
Active member
Re: tach surge
yes it is basic but you're learning still so there's no dumb questions. :lol:
There is a single wire connector under the carpet area by the passanger floor, under the dash. It is a single brown wire with a black connector. This is the EST bypass wire.. when disconnected it takes away the computer control of the timing. Start the truck with that connector unplugged. With a timing light you will need the verify the dizzy is set at 0 degrees advanced, Do I need to be more basic?
yes it is basic but you're learning still so there's no dumb questions. :lol:
There is a single wire connector under the carpet area by the passanger floor, under the dash. It is a single brown wire with a black connector. This is the EST bypass wire.. when disconnected it takes away the computer control of the timing. Start the truck with that connector unplugged. With a timing light you will need the verify the dizzy is set at 0 degrees advanced, Do I need to be more basic?
Chedarbob90
White Trash Racing
Re: tach surge
Anywhere from $30-$60, and you get what u pay for... napa, schucks, vatozone, whichever...
Anywhere from $30-$60, and you get what u pay for... napa, schucks, vatozone, whichever...
BoostedSUV
Active member
Re: tach surge
any auto parts store should sell one or you could probably even rent one to use. It's been a while since I've purchased a timing light so I'm not sure what the going rate is. I also have more high tech timing lights. You could check Jegs or Summit Racing for an Idea on price...you just need a basic timing light, it doesn't have to be adjustabe. Once you get one and need more help just ask.... I have more patience to answer "simple" questions than most do on here. Do a search though, there's plenty of info on here on "setting timing basics." I would definitely check that before you go any further buying parts :tup:
any auto parts store should sell one or you could probably even rent one to use. It's been a while since I've purchased a timing light so I'm not sure what the going rate is. I also have more high tech timing lights. You could check Jegs or Summit Racing for an Idea on price...you just need a basic timing light, it doesn't have to be adjustabe. Once you get one and need more help just ask.... I have more patience to answer "simple" questions than most do on here. Do a search though, there's plenty of info on here on "setting timing basics." I would definitely check that before you go any further buying parts :tup:
