93 ext w/ 4.0 156k miles. Rough, body shaking idling in D, and upon acceleration clackety-clack clattering up to about 2000 rpm, then it clears its throat, and is reasonably OK over 2000 rpm. Did the carbon clean about 10K miles ago and today drove 6 miles at 75 mph in D or at about 3,400 rpm to burn out carbon. No difference. Is worse with the A/C on. Checked all vacuum hoses and they seem to be OK. Haven't read the codes yet - should I begin here?
Wife fed up with this old clunker, and wants to dump it. HELP!

 

Welcome to the Aerostar Forum

autozone and some other auto parts houses will pull codes for free, helps with diagnosis. post and we will try to help.

low-mid rpm roughness and missing, sounds like ignition problems or
vacuum leak.

how long since plugs&wires changed? 4L's high engine compartment heat eat wires.
4L's love Motorcraft ign. wires and double platinum plubs.

150k, vacuum hoses breaking down from heat and years, replace all, 1 hour and a $5 spool of hose, one probably has split-tear or collapsing. check the auto tranny vacuum modulator hose for ATF pulled up into engine

may be leaking intake plenum manifold. get a can of spray carb cleaner with long spray tube and spray along head-plenum seal, rpm increase=leak.

run a can of Seafoam thru it or a pint of water, operating temp engine, pull in whole can of Seafoam thru break vacuum assist hose at 2k rpm and let set for an hour, then run hard on freeway for 20 miles. water pull in slowly at 2k rpm over 5 minutes.

run a 20 oz bottle of Chevron Techron or Regane thru gas to clean injectors and intake valves.

should be good to go another 150k

 

The MAF and IAC are dirty I beat. Try cleaning them real good with CRC cleaner.

 

Thanks, 96_4wdr and Muffinman!

Will have codes pulled and post.

History: replaced plugs & plug wires at 107K miles, 07/01, then only plugs again 08/04 144K, so wires are 5 years 50K miles old. Time to replace?
Also did decarbon as described by CowboyBilly9Mile here:
https://www.ford-trucks.com/forums/showthread.php?t=100739&highlight=pinging

Oxygen sensor replaced at 146K. MAF cleaned at same time. Have read the posts on replacing IAC, but not how to clean it. How do you?

Will have to figure out where the auto tranny vacuum modulator hose is.

How to get at the vacuum hoses that disappear into the blower (?)?

Thanks, guys!

 

50k on plug wires is about max. especially in hot climates or towing apps in a 4L Aero. Motorcraft OEM only, longest life and least problems.

did decarbonizing per Ford TSB stop all the pinging for awhile?
if not, there is more carbon in there, Ford went to a new head design in '95 on 4L which appears to have helped the carbon buildup problem
most on Aero forum use Seafoam, it also cleans the ring pack for better compression seal and is cheaper that the Ford stuff. Suck up whole can thru brake booster vacuum hose over 2 minutes at 2k rpm, turn off and let soak for 1 hour at least, take to the freeway for 20 mile run, WOT 3>4 times and 4000 rpm plus.

Idle Air Control valve on driver side of throttle body, silver aluminum held on by two bolts with electrical plug on end. remove and spray interior with throttle body cleaner. Ford manual says unable to clean replace only but many have success cleaning.
clean MAF again, replace PCV valve, many hi mileage Aero's have enough blowby that they contaminate the MAF and IAC often especially if ring pack is plugged with carbon and combustion crud.
run a 20oz can of Chevron Techron concentrate injector cleaner or Regane injector cleaner thru tank of gas. injectors in Aero's plug and distort spray pattern often, poor fuel atomization=poor running engine with carbon buildup. these two have the Right Stuff to really clean injectors, amine. those cheapy kerosene, lighter fluid alcohol in a $5 bottle are worthless.
I now have mine on a diet of FP60 in the gas and LP20 in the oil for cleaning. Techron every 10k.

auto tranny vacuum modulator on A4LD is on drivers side of tranny near middle, vacuum line runs from mod up to vacuum distribution tree on intake plenum top rear of engine.
see:
http://www.transtarindustries.com/FileStore/pdf/A4LD_04%20W.pdf

vacuum lines inside heater assemble are ok, not subjected to severe underhood temps. cut at heater and replace outside section.

 

Thanks! All great info. Decarbonizing didn't seem to make any difference. What does WOT 3>4 times mean?? Is PCV valve accessed from engine cover inside of van?

Will there be a code to pull even if check engine light isn't on?

Again, thanks!

 

Wide open throttle ... floor it!

 

Re CEL code: In my county (Dade, FL) Autozone, etc are not allowed to diagnose codes, so we have to drive to next county (Broward). If the CEL has not come on, will there be a code to pull?

 

With gas so expensive these days, buying a code reader for $30 may be cheaper than driving to the next county. And yes, even with the CEL off, there will be a code stored in there to pull if it had gone on recently.

 

Any recommendations on preferred or favorite code reader?

I see a digital Innova 3145 online for $35

 

$35 is a good price. Just make sure the guy doesn't charge you $200 for shipping and handling

 

see for list of retailers
http://www.iequus.com/sales/wheretobuy.asp
Krager/Schucks/Checker has same one for $30

run a cylinder balance test after you get the code reader OBD1 tester

 

Ordered at www.partsamerica.com for $29.99 + $6.83 shipping. Downside is it won't be here til 9/14/05 so will have to wait a week to diagnose further.

 

Next time you order from partsamerica.com, choose the "pick up" option when you check out. They allow you to pick up the order after 1 hour at a Kragen/etc... store of your choice, you don't have to pay for shipping, and the price is lower than if you buy it at the counter. It really works for me. You just have to pay for it online with a credit card bring a printout of the order after 1 hour.

 

nice thing about partsamerica is they show which stores have particular item in stock, saves lots of running around. We have the Schucks portion of partsamerican here in SW Washington, about 10 stores to pick from in 20 mile area, really helps the DIY'er