1988 Mustang 5.0 timing issue / popping spitting - Ford Mustang Forum
 
LinkBack Thread Tools
post #1 of 2 (permalink) Old 01-10-2010 Thread Starter
Rookie
 
irishale's Avatar
 
Joined: Jan 2010
Location: Siler City
Posts: 1
 
1988 Mustang 5.0 timing issue / popping spitting

Ok, I have a weird one (for me anyway). First, the car: 1988 GT convertible, 5 speed. 121k miles. I do not know the history of the car/engine, however it appears to be stock, mostly original!

Now, for the problem: I do have an idle problem, and also an ignition problem. First the idle problem: idles between 1100 and 1500 rpms. i cleaned the IAC, checked the TPS, and reset the idle settings by disconnecting the battery/etc. No effect... so I unplugged the IAC. Idles much lower now, sometimes around 800 but sometimes as high as 1100.

BUT... under load below 2500 rpms, sometimes it hesitates and pops... can't tell if it's popping back through the intake or out the exhaust. It does this after it has warmed up. SOMETIMES it doesn't do it and runs fine, but most of the time lately it does this (it's getting worse). Engine feels like it's hestating a bit until it gets close to 3700 or so, then clears up.... so much in fact that it instantly smokes the tires in 1st if the throttle is 3/4 to full WOT. (car has 3.08 'airplane' rear end gears)

Today I replaced the distributor cap and button, as the contacts inside the cap were a bit corroded. No change.

So, tonight I was at the folks' and we checked the timing. Or tried to. I pulled the the advance terminator plug and we hooked up to #1, and couldn't see the timing mark around the tang near the harmonic balancer towards the passenger side of the engine. We thought it was due to surface rust on the HB, so we found the mark and marked it with crayon.

Still couldn't see the mark. Got to looking around, and found it... 180 degrees nearabouts (hard to tell for sure) from where it should be. Soo.... how can this be? The engine has a VERY slight vibration, but not enough to make me think the HB has spun. Aren't the HB's keyed on these engines?

Anybody got a clue what's going on with the HB? And what else should I be looking for that's causing this popping problem?
irishale is offline  
Sponsored Links
Advertisement
 
post #2 of 2 (permalink) Old 01-10-2010
PONY Member
4.6L Member
5.0L Member
 
flatratetec's Avatar
 
Joined: Jul 2009
Location: Northern
Posts: 576
 
HB is bound with rubber and they do spin when they go bad. Set #1 at TDC on the compression stroke and see where the balancer mark is and also make sure that the rotor is lined up with #1 on the cap. Start there and once all that is right you can move on to setting base idle and TPS.

2003 Mustang GT - All the usual engine bolt-ons, brakes and a road race suspension - SOLD
89 5.0 LX - Too much to list, goes fast, turns and stops!
1999 F-350 Modded 7.3L DIT
flatratetec is offline  
Sponsored Links
Advertisement
 
Closed Thread

Tags
harmonic balancer , idle , popping noises , timing

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Ford Mustang Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

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

Password:


Confirm Password:
Email Address
Please enter a VALID email address for yourself, otherwise you will not receive the necessary confirmation email needed to confirm, validate and activate your new AFM member account.

Failure to provide a VALID email address, will result in the cancellation of your new AFM member account registration.

Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



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

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

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


1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182