Bronco lack of power

[Lotus]

Hello!

I have just picked up a "new" Bronco here in Norway.

Model year 1988 with the 5,0 302 engine.

I feel the engine is not as powerfull as my last Bronco even it has the same motor.

It feels like there is something holding it back. Its worse in uphill and using the accelerator heavy.

The check engine lamp does not come on during the driving but my codes are:

KOEO: 33 (EGR problem??)

KOER: AIR system inoperative. Does not know what this mean.

I haven't checked a thing jet. Maybe a tip of where to start?

Tnx!

 

[Skitter302]

The 302 is the most under tuned engine from the factory. Its a perfect engine but Ford fail'd to make it good from the factory.

Big question is, How many miles you have? And then the other questions follow,

are your valves getting full lift?

Is your Cam worn down?

I feel the engine is not as powerfull as my last Bronco even it has the same motor.

Axle ratio makes a difference. Larger ratio i.e 3.55 vs 3.73 can make a difference on the butt dyno.

Maybe a tip of where to start?

Hmmm...

KOEO: 33

Try Cleaning the EGR. it could be stuck because of carbon.

What ever you do don't Seafoam or do any engine "cleaners" you'll just damage what ya have. Trust me.

btw, Nice Bronco /emoticons/[email protected] 2x" width="20" height="20" />

 

[miesk5]

yo,

DTC 33 is triggered when the EVP sensor is not closing; so EZiest & cheapest checks are to inspect & repair/replace repair any bad vac lines

for a quick  vac  hose test; I pull them off gently and use the straw sucking test; one finger over one end and  try to puill a vacuum in the hose

EVP pic in an 88 ; Miesk5 Note EVP is light gray & attached to the top of the EGR Valve

Source: by Travis L (kemicalburns) at



Testing by Ryan M

http://web.archive.org/web/20120121075714/http://www.oldfuelinjection.com/index.php?p=35

See Vacuum Line Acronyms, leak test & gauge pic at  http://broncozone.com/topic/23994-90-58l-getting-continuous-code-33-and-running-code-44/

The EGR Valve Position (EVP) Sensor used exclusively by Ford, can be the cause of driveability problems without ever setting any trouble codes. The relationship between the EVP sensor and the EGR valve is important to understand. Either one being out of spec can cause similar symptoms. Understanding this relationship will help you to diagnose uncoded driveability problems like stumbles, hesitations, rough idles and stalling.

Consider Ford Fuel Injection and Electronic Engine Control: How to Understand, Service and Modify, 1988-1993; & Ford Fuel Injection and Electronic Engine Control: How to Understand, Service, and Modify All Ford-Lincoln-Mercury Cars and Light Trucks, 1980 to 1987 by Charles Probst

avail @ BARNES & NOBLE, AMAZON, E BAY, ETC.

 

[miesk5]

Part II;

Is other Code 44?

Thermactor Air Injection system inoperative

This is a code for the air injection system (smog pump). It should not affect driveability unless it is caused by a vacuum leak
 

Vacuum Leak Symptoms, General; "...Too fast an idle speed; A rough idle or stalling; Hesitation or misfiring when accelerating; An idle mixture that defies adjustment (carburetor)

Vacuum Gauge Diagnosis
Source: by jerickweb

http://jerickweb.50webs.com/autobin/vacuum_meter.html

Vacuum Diagrams & Calibration Parts List for 88 & UP in the Vehicle Emission Control Information (VECI) Decal; Contains Vacuum Diagram & Calibration Parts List for 88 & UP. On-Line for Free at Ford. Click "Quick Guides" in left panel; Scroll to & CLICK VECI Labels "Provides Vehicle Emission Control Information (VECI) and a related calibration parts list." Enter applicable info (need to know your Calibration number from your B-pillar sticker). Vacuum Diagram is the same as the one on the core support or hood or air filter cover. Suggest Right Clicking this Hot Link & Open in New Window
Source: by Ford

https://www.motorcraftservice.com/vdirs/retail/default.asp
 

 

[Rons beast]

Hey Lotus,

I like to look at the simplest things first.  Check for vacuum leaks, check and set the timing to correct specs. 

A simple vacuum gauge connected to manifold vacuum will tell you plenty.  If the gauge is reading 18-22hg at idle with a steady needle your internal engine components are good.

A bouncing needle is an indication of an engine miss, bad valve, broken valve spring and other internal ailments. ( but you would have noticed drivability problems other than just lack of power.) 

Run the engine speed up to about 2000RPMs.  If the vacuum rises then falls off there is a good chance your exhaust system is a problem. Most likely the cat is clogged.

The only true check for that is removal of the exhaust and drive.

Good Luck

 

[Lotus]

Hello again. /emoticons/[email protected] 2x" width="20" height="20" />

Thanks for replying. 

It has about 117 000 miles. Not so mutch for an old car. hehe.

I have done som minor checks. I found out that the spark cable between the coil and the distributor was corrosed. I cleaned it and aplyed some grease inside the cable.

The truck is now mutch more powerful in low rpm's but it still hesitate when giving some gas.

Im going to check the vacume lines in a few days. /emoticons/[email protected] 2x" width="20" height="20" />

 

[Lotus]

However: If it turns out it is the EVP sensor. Is it ok to block it? Or should i buy a new one.?

 

[Rons beast]

However: If it turns out it is the EVP sensor. Is it ok to block it? Or should i buy a new one.?

I would buy a new one.

 

[Lotus]

Today i finaly found the problem. It was the fuel pressureregulator that did most of the problems.

So i changed it, adjusted the ignition timing from 5 to 10 degreed.

Now the truck goes like a dream. In one uphill nearby i used to do 40 mph, now it can do 65mph. Up the same hill. I am happy.

 

[Rons beast]

Congrats....I'm happy for you.   Thanks for posting the solution to the problem.