slight misfire
- Thread starter atkonkler
- Start date
BoostedSUV
Active member
Re: slight misfire
Change the plugs? What gap?
Change the plugs? What gap?
syclone809
Member
Re: slight misfire
Firing order off, tps sensor, ignition module, bad wire, cracked plug
Firing order off, tps sensor, ignition module, bad wire, cracked plug
alwayscode390
pppssssshhhhhtttttttttttt
Re: slight misfire
Every Syclone or Typhoon I have heard run has what you are talking about ... I have never heard a smooth running 4.3 turbo engine.
I had a new distributor, cap , plugs, wires, coil, ecm, and fuel filter installed and it still idles the same, lol ... this is on an engine with 70k miles.
It may be a cracked vacuum line ---
Every Syclone or Typhoon I have heard run has what you are talking about ... I have never heard a smooth running 4.3 turbo engine.
I had a new distributor, cap , plugs, wires, coil, ecm, and fuel filter installed and it still idles the same, lol ... this is on an engine with 70k miles.
It may be a cracked vacuum line ---
cloneman315
Active member
Re: slight misfire
Try to chabge out the dis with a unit from autozone,I have had this fix a bunch of trucks
Try to chabge out the dis with a unit from autozone,I have had this fix a bunch of trucks
Re: slight misfire
If the spark plug wires are not in the plastic looms and are not routed correctly, one or more of the wires can cross fire or short to ground. . This is a particular problem with modern High Energy Ignitions.
Example:
One of my ignition wires (#2) was out of the wire loom and was too close to the exhaust manifold. I did not notice any arcing or misfire until the wire finally made contact with the the hot exhaust manifold while running at highway speed, and began to intermittently ground the ICM. I pulled over and found the wire and the insulation was burned. I rerouted the wire and that fixed it but I still need to replace #2 ignition wire because the insulation is damaged where it contacted the hot exhaust manifold. .
I made custom fitted wire sets using Delco-Packard 535 or Delco-Packard 440 solid core wire in 25 ft. spools and used that wire on ourJr. Fuel dragster's Joe Hunt - Scintilla magneto and on my old points type distributors when it was nearly impossible to keep the wires off the tubular headers. The Packard 535 wire has fire proof insulation but neither type ignition wire can be used on modern vehicles because that wire is not shielded and the RF interference will cause errors and problems with the electronic sensors and control modules..
If the spark plug wires are not in the plastic looms and are not routed correctly, one or more of the wires can cross fire or short to ground. . This is a particular problem with modern High Energy Ignitions.
Example:
One of my ignition wires (#2) was out of the wire loom and was too close to the exhaust manifold. I did not notice any arcing or misfire until the wire finally made contact with the the hot exhaust manifold while running at highway speed, and began to intermittently ground the ICM. I pulled over and found the wire and the insulation was burned. I rerouted the wire and that fixed it but I still need to replace #2 ignition wire because the insulation is damaged where it contacted the hot exhaust manifold. .
I made custom fitted wire sets using Delco-Packard 535 or Delco-Packard 440 solid core wire in 25 ft. spools and used that wire on ourJr. Fuel dragster's Joe Hunt - Scintilla magneto and on my old points type distributors when it was nearly impossible to keep the wires off the tubular headers. The Packard 535 wire has fire proof insulation but neither type ignition wire can be used on modern vehicles because that wire is not shielded and the RF interference will cause errors and problems with the electronic sensors and control modules..
atkonkler
Is this your bush?
Re: slight misfire
Is anyone in mn? id like some help with this problem! Quertyphoon is off on business for a while! just wanna meet someone who is as crazy as i am about these beasts! Does our cams lope make it seem like a misfire? Is this a possibility? i just dont have a can tool or data master to look at stuff
Is anyone in mn? id like some help with this problem! Quertyphoon is off on business for a while! just wanna meet someone who is as crazy as i am about these beasts! Does our cams lope make it seem like a misfire? Is this a possibility? i just dont have a can tool or data master to look at stuff
alwayscode390
pppssssshhhhhtttttttttttt
Re: slight misfire
The cams are pretty mild.
Mine feels like a miss , I can feel it shake the engine and the truck a tiny bit when it happens ---
The cams are pretty mild.
Mine feels like a miss , I can feel it shake the engine and the truck a tiny bit when it happens ---
atkonkler
Is this your bush?
Re: slight misfire
Im totally lost! need help! im ready to put the sensative bitch on jack stands and start dismantling it! so your idle flutters alittle im talking miniscule at idle? I put my hand on the hood and you can feel it but not to much i think its just the way our trucks run if you ask me! Can someone tell me how to properly do a boost launch ive never really attempted one!
Im totally lost! need help! im ready to put the sensative bitch on jack stands and start dismantling it! so your idle flutters alittle im talking miniscule at idle? I put my hand on the hood and you can feel it but not to much i think its just the way our trucks run if you ask me! Can someone tell me how to properly do a boost launch ive never really attempted one!
Re: slight misfire
Syclones and Typhoons are equipped with the same camshaft at the 1988-1993 LB4 engines and they are very mild and run very smooth. Your problem appears to be a vacuum leak.
Syclones and Typhoons are equipped with the same camshaft at the 1988-1993 LB4 engines and they are very mild and run very smooth. Your problem appears to be a vacuum leak.
Re: slight misfire
Before I get burned at the stake for heresy, I must retract my statement where I wrote "Syclones and Typhoons are equipped with the same camshafts as the 1988-1993 LB4 engines"
According to my "1991-1993 General Motors Illustrated Master Parts Catalog", the 1991 Syclone ZR9 and 1992-1993 Typhoon Z79 were equipped with a different camshaft (p/n 10144176) than the 1991 LB4 (p/n 10088148).. However, the 1992-1993 LB4 engines were equipped with the same camshaft as the 1991 Syclone and 1992-1993 Typhoon (p/n 10144176).engines. The difference between the 10088148 and 10144176 camshaft was insignificant and 100% of the power increase came from the turbocharger alone. I understand this subject has been well covered in the past by the " numbers crunchers".
The point I tried to make was that so-called "Syclone or Typhoon camshaft" will not make the engine lope like it has a miss or vacuum leak. .
Before I get burned at the stake for heresy, I must retract my statement where I wrote "Syclones and Typhoons are equipped with the same camshafts as the 1988-1993 LB4 engines"
According to my "1991-1993 General Motors Illustrated Master Parts Catalog", the 1991 Syclone ZR9 and 1992-1993 Typhoon Z79 were equipped with a different camshaft (p/n 10144176) than the 1991 LB4 (p/n 10088148).. However, the 1992-1993 LB4 engines were equipped with the same camshaft as the 1991 Syclone and 1992-1993 Typhoon (p/n 10144176).engines. The difference between the 10088148 and 10144176 camshaft was insignificant and 100% of the power increase came from the turbocharger alone. I understand this subject has been well covered in the past by the " numbers crunchers".
The point I tried to make was that so-called "Syclone or Typhoon camshaft" will not make the engine lope like it has a miss or vacuum leak. .
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