Spark Plugs - Off-Road Forums & Discussion Groups
Ford 67-96 F-Series, 78-96 Bronco All discussions of 67-96 F-Series Trucks and 78-96 Broncos

LinkBack Thread Tools Display Modes
post #1 of (permalink) Old 12-15-2001, 06:29 PM
Posts: n/a
Spark Plugs

I have a miss under load (low RPM, trying to accelerate...especially up hill or with the A/C on). I've read some previous posts about this and the first place I want to check is the plugs (old Bosch platinums) and the timing. My engine is the 351W/E40D combo. I use a MSD Blaster coil with Accel cap and rotor(just changed) and Taylor Spiral Core wires. Seems like it came on a while after making the change to the MSD/Bosch/Taylor combo a couple or years back. Any thoughts as to what might cause the miss and what kind of plugs to get??? I've heard that Bosch aren't the best for Fords and that Motorcraft or Autolite are the best. Any imput would be great. Thanks

Sponsored Links
post #2 of (permalink) Old 12-15-2001, 06:49 PM
Join Date: Apr 2001
Location: eustis , Florida
Posts: 1,444
Thanks: 0
Thanked 0 Times in 0 Posts
Re: Spark Plugs

Get the boschs out. I had tried a set of those and after a month, the platinum tips were disintegrating. Although i currently have a problem similiar to yours(missing at low rpms at cruise up a hill), mine i know is my fordracing 9mm wire set. I am currently using AC Delco Rapid-fires but im told by Ford performance experts to only use Motorcraft or Autolites as you said, and not to waste your money on any of those fancy plugs. My last set of wires were arcing through the boot to the exh. manifold causing a miss and i know this warranty replacement set is now doing the same thing, but i haven`t pinned down which wire is malfunctioning yet.
Im also wondering if theres any *truth* to that plasma formation under my accel cap since their not vented like stock ford ones as mustangs and fastfords magazine tech article pointed out.[img]/wwwthreads_images/icons/crazy.gif[/img] Maybe i will try a stock cap and see.

But pull out some of those Bosch`s and with a good light and a magnifying glass, inspect that little platinum tip and im sure you`ll find them burn`t up just like i did.
Im running a Crane ignition system w/high output Fireball coil, but my wires were malfunctioning even with the ign. system bypassed.


BRONCOMANIA is offline  
post #3 of (permalink) Old 12-16-2001, 02:06 PM
Posts: n/a
Re: Spark Plugs

The first place to look is the plug wires when they take a dump that is how they act thew will miss under load but work ok at cruse had fits once had new wires and that prob.and i used a set of used wires and tryed it and worked fine took the new ones back and got good wires.good luck Bill

Sponsored Links
post #4 of (permalink) Old 12-16-2001, 04:59 PM
Join Date: Mar 2001
Posts: 975
Thanks: 0
Thanked 0 Times in 0 Posts
Re: Spark Plugs

I tried the Bosch Platinums too. They worked great in the Dodge Caravan, but in the 89 351W, not so good. It runs like crap until it warms up, but always idles like crap. It ran fine with the Motorcrafts.

The trouble with being on top...You always have to look over your shoulder. The best never rest. Fear the FORD thunder!!!
MY2ND78 is offline  
post #5 of (permalink) Old 12-17-2001, 01:04 PM
Join Date: Mar 2000
Posts: 1,034
Thanks: 0
Thanked 0 Times in 0 Posts
Re: Spark Plugs

I 2nd the AC Delcos and motorsport wires. Worked great for me so far.

90 BRONCO Custom
6" Superlift w/Steering System
35x14.50 SSR's
Shovel is offline  
post #6 of (permalink) Old 12-17-2001, 02:49 PM
Join Date: Dec 2000
Posts: 920
Thanks: 0
Thanked 0 Times in 0 Posts
Re: Spark Plugs

I'm running the Accel header plugs,coil and, Ignition System. Once I figured out the correct plug gap and the Correct timing, Every thing is good- I idle at 675 and real smooth. It also gave me better throttle response.

<font color=blue>Backyard Builder-If I ain't drivin it I'm under it!<font color=blue>
slickerthanyou is offline  
post #7 of (permalink) Old 12-18-2001, 12:24 AM
Join Date: Sep 2000
Posts: 1,147
Thanks: 0
Thanked 0 Times in 0 Posts
Re: Spark Plugs

One more vote for ditching the Bosch Platnums

They haven't run well on anything I own. Currently running A/C Delco plugs, gapped out to .060 to take advantage of the MSD-6 and TFI style MSD blaster coil. Like others I'm running those sale priced Crane wires someone(think it was Steve) tipped us off to last Spring. I've pulled three off the plugs leaving the boot and end on the plug, but crimped them back on no problem.

You can take the wires in to get them tested for resistance value, most places will do that free for you. I'll probably spring for a new set of Jacobs wires and one of their super thick (well insulated), real brass terminaled caps and rotors next Spring.


What are the Bosch gapped out to ?

Sixlitre is offline  
post #8 of (permalink) Old 12-20-2001, 06:17 AM
Mud in my Veins
Steve83's Avatar
Join Date: Dec 2000
Location: Memphis, TN
Posts: 5,301
Thanks: 0
Thanked 0 Times in 0 Posts

Nope - I can't take credit for that tip. But I got 2 sets of wires.[img]/wwwthreads_images/icons/smile.gif[/img][img]/wwwthreads_images/icons/smile.gif[/img][img]/wwwthreads_images/icons/smile.gif[/img][img]/wwwthreads_images/icons/smile.gif[/img][img]/wwwthreads_images/icons/smile.gif[/img][img]/wwwthreads_images/icons/smile.gif[/img][img]/wwwthreads_images/icons/smile.gif[/img]

[email protected]
Steve83 is offline  
post #9 of (permalink) Old 12-20-2001, 03:47 PM
Join Date: Mar 2001
Posts: 2,074
Thanks: 0
Thanked 0 Times in 0 Posts
Re: Spark Plugs

Sixlitre is the one who gets the credit for the Crane Wire sale back in March!


The main difference in my truck and yours is your truck is a toy and my truck is a truck!
havack is offline  
post #10 of (permalink) Old 12-20-2001, 11:14 PM
Mud in my Veins
muddybronco's Avatar
Join Date: Oct 1999
Location: woooooo pig sooooooie!
Posts: 6,842
Thanks: 0
Thanked 0 Times in 0 Posts
Re: Spark Plugs

Oh that's funny. Sixlitre gave props to steve, but he was the one who actually dug up the deal for everybody! If i dont bust my budget on the axle swap i should be able to get a MSD coil, new wires, and new plugs at .060. Hopefully that will kick me up 1 mpg or so... wishful thinking. I just replaced my check valve on the crossover tube and WOW it's like somebody took my truck and turned the treble all the way down and the bass all the way up! I can actually hear my exhaust rumbling at idle now and i get a loud drone inside with the windows up on the highway, but that's a good sign! I can still hear the cat pumping out exhaust though. What kind of hose can i use to connect the air tube to the cat? It's only ~6" but it needs to be high temp of some kind i would think. And i had a good first experience at Advance, but they didn't have 1/8" rubber hose for vac lines, just 7/64 or something that was WAY too small. But it doesn't feel very heat resistant. Havack, what was that line you got at FORD by the foot? I think that might work better because it's not as big on the outside... even this small tubing (i got a 2 inch sample) is kinda big on the outside, despite being too small I.D. I think i'm gonna pull my PS pump this weekend and do a drive-by... I'm not sure if i want to get a free replacement or spend more $$ and get another one at advance or napa. Are there any GOOD ones at these stores, and/or does ford carry a NEW one that's not 500 bucks? Maybe I should order an AGR and be done with it???

S H O U L D A G O T T A F O R D!
muddybronco is offline  
Sponsored Links

Quick Reply

Register Now

In order to be able to post messages on the Off-Road Forums & Discussion Groups forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:


Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome