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2000 safari engine acceleration problem

4K views 10 replies 5 participants last post by  High & Dry 
#1 ·
Picked up a 2000 Safari cargo windowless that I plan to customize. It was owned by the city of Ventura Ca. Van is in mint condition (not a scratch on it outside or in) driven by a civil engineer (have the documentation) probably garage kept, with only 82,000 mi (almost new for this type/age of van). Test drive was good but short (what could be wrong, this thing is like new). Had a two hour ride home to San Diego and was experiencing difficulties in speed/acceleration when any incline was involved (at the time thought I just was'nt familier with the van). Long story long since then it's not the fastest off the line (larger engine and alot lighter than my Dodge Ram 1500 V6 but slower) and acceleration from 30mph to freeway speeds is worse, especially if there is an incline (can't get over 50mph until terrain flattens out, I mean old ladies in Saturns whizzing past me and everyone trying to get around me). Also get terrible gas milage, 12mpg combined when stats. predict 17mpg. Does anyone know why this is?
 
#2 ·
Probably combination of everything involved.These things detuned from factory and never were power houses.But Things to look at are Dirty sensors Oil in plenum from PVCs Mass air flow sensor dirty EGR.Mine used to drop to second climbing a hill near my house at fifty and several customers vans did same thing at same place.Now I can climb it in fourth with converter locked.So there are things to improve performance.
 
#3 ·
With loss of power on hills, look at a dead/dying cat, possibly caused by possible leaking/sticky poppet valve in the injector. You might check your O2 sensor, too.
 
#5 ·
Is common to only get 80,000 mi out a cat? I've always driven used vehicles and don't know exactly how long they last. Replaced one on my last van and it was pretty pricey. Here in California Idont think you can sell or plate a vehicle and I just bought this.
 
#6 ·
Cats don't just die; they're killed. If there was an unattended leak inside the plenum dumping raw fuel into the exhaust, the cat would quickly die.

This is just one of the possibilities, however.
 
#9 ·
plebanski said:
experiencing difficulties in speed/acceleration when any incline was involved Long story long since then it's not the fastest off the line (larger engine and alot lighter than my Dodge Ram 1500 V6 but slower) and acceleration from 30mph to freeway speeds is worse, especially if there is an incline (can't get over 50mph until terrain flattens out, I mean old ladies in Saturns whizzing past me and everyone trying to get around me). Also get terrible gas milage, 12mpg combined
Aside from all the above how well it runs ???????
Your first mistake is assuming ,,,they may have changed oil regularly, but obviously there is some problems ,,all could possibly be fixed with a tuneup and maintenance , you won't know what is wrong until you start investigating , pull a couple plugs #1 and a couple others , wipe the inside of tailpipe and see what is on your finger ,pull the dist cap and inspect for arcing and or corrosion , If it were my van I would give it a major tune up , and fuel filter to start with , , Like Leann said cats don't just die ,they're killed , something has been neglected ,
you may have a real Jewel there , treat it like one and it will be good to you :mrgreen:
 
#11 ·
Hi, my experience may be of some help to you. My 99 Astro suffered the exact symptoms, fine at idle, fine at slow speeds, but push the pedal for anything demanding more jam and all you get is noise, some pinging, weird delayed tranny shifts, but no acceleration to speak of. Here is what I did to rectify the problem, and yes, all steps are relatively easy for anyone who knows the basics. :banana:

You engine light may or may not be coming on, I found that by finally driving the youhoo out of the van trying the old Italian tune up finally resulted in a check engine light, but if you are just farting around town, you may not get a light. Because a code scan costs a minimum of $50 in my town and I could buy a good OBDII code reader on sale for $69.99, that was a no brainer. Don't just jump to the conclusion that the Mass Airflow sensor is shot, as it tends to affect all RPM and power ranges, not just high demand.

Scanned engine which resulted in three codes 0101, 0300, 0420, manual says all point towards, Mass airflow sensor, engine misfire, and catalytic converter no operating properly. Now one can start replacing a Mass airflow sensor for $300 or take a step back and try a more sensible approach.

1. Look at all connections for loose leads,wires,connections
2. Change the Plugs,wires, cap and rotor if you do not know the last time they were changed or were changed more than 50,000 miles ago. Even if not the cause, now you have a fresh ignition.(~$100.00)
3. Replace the air filter and clean the entire breather box assembly (~$15.00)
4. While you have the breather box out, carefully clean the Mass Airflow Sensor with electrical contact cleaner], NOT CARB CLEANER (~$7.00)
5. Start it up and go for a run, see if it runs properly.
IF NOT
6. While running, tap the Mass Airflow Sensor with a screwdriver handle. If the engine stumbles and then recovers, then YES, The MAF is the culprit, or part of the problem. Replace and take for a drive to see if it runs properly.
IF NOT
7. If your engine didn't stumble with the tap test, there is only one thing left. An exhaust restriction that is probably a plugged/melted Catalytic converter. Have an honest exhaust shop cut it out and replace it with a section of pipe.(~$100.00)

For me, I made it all the way to step 7, My MAF was OK via the tap test and the CAT was melted to allow only about 20% of the exhaust flow.

My old stump puller is back, with more power than it ever had and I have a major engine tune up as a bonus. :layrubber:

Hope this works for you, don't worry, the system is not as complicated as some will lead you to believe, and 90% of power loss issues are related to one of more of the fixes mentioned above.

PS. cutting out the CAT did not cause any Engine Light Issues, my dash is beautifully dark!!

Good luck and happy trails!!
 
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