slow engine deceleration when shifting between gears. any way to stop this from happening?

claytonbretveld
5

Asked by claytonbretveld Feb 21, 2013 at 08:57 PM about the 1998 GMC Sierra 1500 K1500 SLE 4WD Standard Cab SB

Question type: Car Customization

i have a 98 gmc sierra 5.7 5 speed. when i push in the clutch and go to shift to the next gear the rpm hangs there for a few seconds and im sure it has something to do with smooth shifting but it bugs me because im used to driving non electronic vehicles. also if i leave it in gear and clutch still engauged when i let off the gas it takes about five seconds before the engine actually starts to decelerate. is there any way to make the engine rpm drop as soon as i let off?

8 Answers

tenspeed
69,615

There's a dash-pot type of affair that keeps the throttle plate from slamming shut. The slow closing throttle burns the fuel mixture cleaner. I've noticed it too with my manual tranny vehicles.

claytonbretveld
5

well if you rev it up in neutral it drops like it should but if its in gear it has that funny lag before it starts dropping. so i just wondered if i could change that somehow

7jimmy7
14,645

their is a switch under dash that tells the pcm clutch angle ,connected to lever arm,remove and clean or replace,maby cure rev issue

Alex Nazarian
1,085

Possible vac leak, tps or iac issue. Check your DTCs and report back.

claytonbretveld
5

all systems are good no codes or leaks. ive driven a few of these trucks and they all do the same thing so i think its supposed to do it but i dont want it to.

Michael Tutty
5,975

They are designed to do this as part of the emissions control system. It is, in my opinion, plain dangerous in certain circumstances. There is an aftermarket attachment that can be fitted that does away with the throttle lag. I makes a huge difference to throttle response both when you add and when you release. Any good performance shop should be able to steer you in the right direction. Failing that, check LMC.

claytonbretveld
5

do you know what the part is called? cant seem to find anything

Andrew Olsen
9,995

I've driven a few of 5 speed chevy's and they all have done this. The 5 speed trans in these trucks isnt designed to be quick shifted, It normally holds rpm's up after clutch release for only 1 sec. It's normal operation and will only be a problem if you try to float gears or something. It's not a throttle lag as if still in gear it should still decelerate as soon as you let off the pedal. If it doesnt then i'd worry about it. Also when cold it will have a high idle and magnify the effects of this system.

Your Answer

Add photo

Related Questions

  • Computers 1 answer

    What would happen if I took a computer from a 2000 Tahoe with a 350 vortec and put it in a 98 GMC Seirra with a 305 Vortec, would it be like a power chip up grade or would it even start?

    1998 GMC Sierra 1500

    -

    Car Customization

  • transmission shifts hard 11 answers

    5.3 L engine (from 2002 Silverado) with a 4l80e transmission shifting hard from 1st to 2nd gear. All other gears shift normal

    2001 GMC Sierra 1500 SLT 4WD Extended Cab LB

    -

    Maintenance & Repair

  • Speedometer doesn't work and transmission doesn't shift gears. 25 answers

    The speedometer stays at 0 all the time. When the transmission is in drive it won't come out of 1st gear. Reverse works fine, and if I manually put the transmission in 1st or 2nd it works fine. 199...

    1999 GMC Sierra 1500 SLT 4WD Extended Cab LB

    -

    Maintenance & Repair

  • How can I stop my starter from re-ingaging after the engine starts? 2 answers

    After I start my engine and release the Ignition Key, the Starter tries to re-ingage and makes a high pitch grinding sound because of the starter gears and the flywheel gears trying to mesh. What coul...

    1993 GMC Sierra 1500 C1500 Standard Cab SB

    -

    Maintenance & Repair

  • I put my truck into drive or reverse n it will not move at all what is causeing this to happen 62 answers

    2003 GMC Sierra 1500 SLT 4WD Extended Cab LB

    -

    Maintenance & Repair

Sierra 1500
Looking for a Used Sierra 1500 in your area?
CarGurus has 59,664 nationwide Sierra 1500 listings starting at $2,000.
ZIP:

Search GMC Sierra 1500 Questions

GMC Sierra 1500 Experts

#1 dragonflyoffshore
dragonflyoffshore
Reputation 3,030
#2 John Saffrahn
John Saffrahn
Reputation 2,120
#3 Glenn Clingenpeel
Glenn Clingenpeel
Reputation 1,670
View All

Related Models For Sale

Used Chevrolet Silverado 1500"
1,636 Great Deals out of 133,605 listings starting at $999
Used Ford F-150"
2,103 Great Deals out of 121,851 listings starting at $988
Used Dodge Ram Pickup 1500"
599 Great Deals out of 11,938 listings starting at $1,995
Used Toyota Tacoma"
505 Great Deals out of 23,488 listings starting at $1,995
Used Chevrolet Tahoe"
418 Great Deals out of 28,877 listings starting at $2,495
Used GMC Yukon"
207 Great Deals out of 8,192 listings starting at $2,550
Used Ford F-250 Super Duty"
425 Great Deals out of 36,722 listings starting at $3,495
Used Jeep Wrangler"
352 Great Deals out of 42,092 listings starting at $1,800

Used Cars For Sale

2015 GMC Sierra 1500 For Sale
42 Great Deals out of 42,318 listings starting at $21,439
2014 GMC Sierra 1500 For Sale
96 Great Deals out of 3,607 listings starting at $18,800
2013 GMC Sierra 1500 For Sale
110 Great Deals out of 2,798 listings starting at $14,729
2012 GMC Sierra 1500 For Sale
76 Great Deals out of 2,147 listings starting at $12,995
2011 GMC Sierra 1500 For Sale
83 Great Deals out of 1,971 listings starting at $9,995