'97 Grand Marq- Snap, CACKLE, pop

Hello All:
My '97 GM (190k miles) is cackling so badly in hot weather I'm almost afraid to drive it- I've switched to plus grade gas and even that isn't
helping. If this was an old car you would just set the timing back a few degrees, but since the timing isn't adjustable, what do you do? Do I have to take the heads off and have the deposits it undoubtedly has scraped out? It runs like a top but I'm afraid I'm going to burn up valves or damage the pistons going like this. CN
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Chris Nagorka wrote:

have you checked the OBD-II for any codes? This may help diagnose the problem.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Thu, 30 Aug 2007 07:33:37 -0400, snipped-for-privacy@webtv.net (Chris Nagorka) wrote:

I suspect you have one or more of several problems. First, clean the MAF sensor. The throttle body and IAC also probably need cleaning. This can be done when you clean the EGR ports if you have never done this. Make sure the PVC system tubing is open and the tubing is in good condition. They tend to crack near the throttle body and become plugged with carbon and sludge. This is almost never a timing issued on these engines.
Lungnut
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Chris Nagorka wrote:

http://www.tccoa.com/articles/intake/mafclean.html
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
I'll take a look, thanks for the suggestions.
CN
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Chris Nagorka wrote:

You can pick up the T-20 tamper proof torx bit at most auto parts stores. The whole operation takes only about 15 minutes and is easy. Just handle the MAF with care.
The improvement is usually amazing.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.