[bogus]

'83 Safari conversion 4.3 102,000 miles

The engine has been down in power and knocking a bit. I've had it just over a year. I figured first I'd change the air filter, cap, rotor, plugs and wires.

After looking under the rear cover I realized I'd have to have the hands of a five year old with the strength of body builder to get the plug wires off and the forward plugs changed. There is no clearance. How do you get in there? I looked through the paper work I had and found that the plugs had been changed at 78,000 miles so I just changed the blackened air filter, cap and rotor and decided to see how it ran.

No difference. OK, so old school kicked in and I retarded the timing. I marked and spun the distributor 1/16 of an inch clockwise to see if it would help the knocking and bring any power up at all. The engine idled really rough and chugged and loped and then flooded when I tried to restart it. I put the timing back exactly where it was and the idle is the same. On the road, it runs the same as it did before I did any work on it but it won't idle. If I don't give it a little gas, it will eventually die.

I disconnected the battery and let it sit overnight, reconnected it and drove it about 15 miles to see if the computer would relearn and get the idle back. No luck. I checked it for codes even though the engine maintenance light wasn't on. No codes.

Any ideas on the idle, knocking/pinging and loss of power? It's not like it's totally gutless, it just doesn't have the same get up and go it did....and how do you change those forward plugs?

Thanks

 

[ghostrider1061]

some people get them by taking the front tires off and using a looooong exttenson get them that way. it has been my experience that changing the plugs in ANY van is and will be a major pita. it took me about 2 hours to change my plugs. the pass side was easy, but the drivers side :banghead: :screaming: it took the most tme. i know it looks hard but just give yourself the time and it will pay off. i took the front seats out to give me more room. doing that made it for me better. still a major pita.

 

[astro355]

How does the oil look? Last time it was changed?

Does it have any vacuum leaks?

Are you sure about the year? I thought astro/safaris first year was 1985.

 

[Mr_Bowtie]

Says on the right side column his Van year is '92 not '83?????? :shrug:

I second the Vacuum leak idea!

 

[bogus]

It's a 92. I don't know what was in my head with the 82 and 83 I wrote. Oil has about 800 miles on it. It's rigged as a handicapped van and I only drive it a couple times a week to take my dad around. I did look at vacuum lines and wiring and didn't see anything.

 

[190xtd]

On my 90 Safari I tried to change the plugs from the top. I ended up taking the front tires and inner fender liners off. Had to have my 7 year old reach in and pull the plug wires off and reinstall them. Used a 2 foot extension on the rachet, no problem getting to them then.

 

[Leeann_93]

I go through the wheel wells, using a long pair of wire-puller pliers to get the wires off, then a 9" extension on the ratchet with a wobbly spark plug socket.

It's not too bad that way.

 

[interestingfellow]

Get a guage and check your vacuum against what the manual calls out. Vacuum problems can screw about with a whole lot of different sensors and readings and what not.

I have a bad egr, which effects vacuum, which affects idle. Runs great most of the time, unless I sit still for too long... she idles down a little and then rough idles till I throttle it up a bit.

 

[bogus]

I checked all the vacuum lines and wiring again. I don't find anything off. I drove it and it I finally got an intermittent check engine light at lower idle and a code off of it. #33 MAP Sensor Low Vacuum.

My next question.
When I originally changed the cap and rotor, the inside of the distributor under the cap was rusted and corroded. Removing the rotor took great effort. At one point I was pressing down on the ring under the rotor and at the same time pulling up with my fingers. I looked under the cap again today and noticed that the ring is loose and kind of floppy. I'm not sure what it does in this particular style distributor but surrounds the advance mechanism. I went to a local Pick N Pull and looked at a couple 4.3's there. The ring was snug and fairly tight on those. Some were corroded like mine and some were very clean. I've attached a photo of my distributor.

Is it possible that this is the problem with the rough idle? I know the control module uses information from the MAP to control fuel ratios and timing. What is the purpose of this ring?

 

[bogus]

Photo was there and then went away. Here it is again.

 

[astro355]

I doubt that is your problem but it shouldn't be loose. I would get that replace since you already know that is not right. The code you got points toward either a vacuum leak or clogged vacuum ports. What is the vacuum measurement while the engine is at idle and warm?

 

[bogus]

I'll measure it a little later this morning when the frost melts away but with the way it's pulsing and wanting to die, I'm don't think I can get any kind of a steady reading.