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Discussion Starter #1
Tested the fuel pressure...43 psi engine off but the same with wn gin running and regulator vacuum hose connected. Disconnected hose pressure stays same. Put hand vacuum pump on regulator and with engine running and 25 on vacuum pump still get 43 psi. Seems to be no change in preasure. Could this be why the truck will idle but falls on its face when trying to drive it?
 

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Discussion Starter #2
Changed the regulator now the pressure is normal and it holds pressure when the engine is turned off as opposed to before when pressure dropped to 0 in about 5 seconds.
Now it idles actually worse than before Still has drivable to issues.
If the timing is set to 10 degrees with SPOUT disconnected it will not accelerate it just fires thru the intake and will not rev. If I advance the timing to 20 then it will go but no power and not smooth. I do get some EGR codes 31 and 34 and with the new regulator the vacuum is around 10 so I might have an EGR problem will check tomorrow
Thank you for your help though
 

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I have a similar problem

Do you get both 31 & 34 at the same time?

I have a 34 that never will go away even with new EVp and EGR but I only get a 31 when i pull the connector to the EVP. My engine will start and idle fine but when i touch the accelerator slowly it will hesitate and eventually stall, if I give it plenty it will rev up and then stall.

Is your check engine light on?
 

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Discussion Starter #4
yes, I get the 31 and 34 and the same time. It does sound like we have similar problems. I plan to remove the EGR valve and plug the holes to see if that is the problem (or part of the problem).

I'd look for things that reduce the airflow into (or out of) the cylinders: timing chain slack, loose rockers, worn camshaft, exhaust restriction (overheated cat, possibly from running so rich for so long), low compression...
Steve83 it is a new crate motor so the internal should be good (not ruling it out but on the bottom of the list). I will isolate the EGR but if that does not change anything I will go from there. I am thinking that the O2 might be bad causing the engine to run lean. Also not ruling out the ECM itself but will have to take it a step at a time (this makes a great teaching tool for my 16 year old who the bronco is for and he like learning and working on it). but was hoping somebody might have had this problem and found a solution....
 

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Whenever anybody gets an EGR code, I always tell them to open up the PCM to make sure the board isn't damaged. The capacitors on the board have a tendancy to leak over the circuitry controlling the EGR and will throw out false codes because of it, or not control the EGR properly. Either way, its a problem. Since you installed a crate motor, I don't know if this would be an issue, since you may have a rebuilt PCM anyways, but its worth checking.
 

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Discussion Starter #6
My bad, the crate motor is a stock long block. The motor seems fine since it idled like glass with the old fuel pressure regulator was on it. It would only idle though it did not have any power it would just fire thru the intake when you tried to go (same as it does now). It seems that the extra pressure the old regulator provided was enough to compensate for the extra air it seems to be getting.
I have not changed the PCM but it is not the stock one it is a rebuilt and to make it fun the parts numbers on that PCM have rubbed off.
My plan is to take the EGR out of the equation, if that is not it then head to the sensors (I have checked a few already, the TPS, intake temp sensor, MAP) and change the O2 since it was on their with the old worn out motor. As a side note it acted the same with the worn out motor (the old motor had a ton of blow by it was worn).
 

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Discussion Starter #7
Ran compression test and all cylinders within 3 psi of each other and tested good. This should rule out ma mechanical issue. Will remove the EGR for the next test but I am leaning toward ignition. The distributor is stated correctly I belive as at 10 degrees base timing the module is 45 degrees between the A/C and thermostat housing. If the egr is not the problem I will search for a vacuum leak with starting fluid as we have checked the hoses already. I am leaning toward the distributor also. But before I replace it my son and I plan to check sensors at the ECM connector to try to rule out a short in the harness.
Again any help is appreciated
 
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