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Discussion Starter #1
I am at a dead end here and hopefully someone can line me out.... My ride is a 1990 with 351w and e4od....my problem is I get up to around 2500 rpm on acceleration and I hear a popping coming from under the hood and the exhaust sounds louder under the hood then out the tailpipe and I have series 40 flowmaster for a muffler. Pulled codes and I got a 22 and 33. Put a new map sensor and egr valve along with evp sensor and that took care of those codes but it's still doing the popcorn machine at 2500 rpm and sometimes when I first start it it idles rough and almost dies and just has no power really. Pulled codes again and got an 11 and 34. Thinking it's my cat crapping out but. Wanted to get another opinion. And if it is my cat would it affect anything to just do away with it? Thanks :banghead
 

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penis
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If your cat is clogged it will follow the path of least resistance but I don't think that is your issue with the codes.

Code 11 is system passed

Code 34 is EVP voltage above normal
 

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yo;
Think that "pop" was actually detonation?
DTC 33 & 34 "...DTC 33 is triggered when the EVP sensor is not closing.... To prevent the EGR valve from opening when the engine is cold, the vacuum line to the EGR valve may be connected to an EVP (miesk5 edit) Vacuum is not allowed to pass to the valve until the engine is warm. EGR isn't needed when the engine is cold, only when it is warm and under load. Any of these codes could indicate a faulty EGR valve as well. as well as a problem in the ...vacuum solenoids' Miesk5 note; TAB & TAD; so repair those vac lines 1st..."
Source: by Larry C
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 <$ vac line test; I pull em off and use the straw sucking test; one finger over one end; includes EVP testing & Links
Source: by miesk5 at FSB
http://www.fullsizebronco.com/forum/showthread.php?t=175236
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DTC 34/336 and 35/337 "...mean that the PFE voltage is too high. This could be the result of a clogged exhaust or the PFE sensor itself; The PFE hose should be examined carefully. We have seen them with pinhole leaks. This causes the exhaust pressure to bleed off giving an inaccurate reading to the PFE sensor. They can also deteriorate because of the corrosive exhaust gases they carry. This weakens the rubber and may cause porosity or cracks. A quick check is to hook a vacuum pump to one side and plug the other side to see if it can hold vacuum...."; read more on testing w/DVOM & vacuum pump
Source: by tomco-inc.com http://www.tomco-inc.com/Tech_Tips/ttt34.pdf
 

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Discussion Starter #4
I wrote down the wrong code on that post..sorry. After I replaced egr valve, map sensor was when I got the 34 then I replaced the evp and I cleared my codes went for a drive came back retested and got a 21 which I know is my coolant temp sensor. I have also noticed that when I start it up it runs kinda rough and at 1500 rpms for a while then it will drop to about 600 and lobe and sound like I put a monster cam in it. It also kinda hesitates when you take Off from a stop and stutters while driving down the road..... Hope this helps y'all thanks again:doh0715:
 

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popping can be caused by a lean condition. check your fuel pressure and change your fuel filter.
 

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yo
ok
21 (or): ECT (Engine Coolant Temp) out of range. Engine coolant wasn't brought up to normal operating temperature before KOER portion and/or KOEO or ECT sensor is bad.
If you see some rust in it clean it by sanding the surface using a fine grit sandpaper, Also check the connector and wiring..."

and this is neat by my pal!
Connector Repair Video in an 86 5.0
Source: by JKossarides ("The Bronco", Jean) at http://www.supermotors.net/registry/media/720465

"This measures the temperature of engine, and has a great impact on fuel ratio. This makes simple work of enriching the mixture on start up, overheating, and full throttle fun. It also allows us to lean out the mixture at certain times, to shorten the time it takes to warm up the engine helping us get great fuel economy. The Engine Coolant Temperature (ECT) sensor is a thermal transistor, which means it allows less electricity to pass through the sensor the warmer it gets. The ECT receives the “Signal Return” voltage from the EEC, then allows a certain amount to return back to the EEC. Because the ECT is in direct contact with the engine coolant flow it changes resistance in response to the temperature of that coolant. The ECT is third in command in the hierarchy of EFI sensors, this means this sensor is very important when calculating fuel ratios and timing curves. This is because of simply chemistry; fuel and spark are constants in the equation. Air is the biggest variable in combustion; it changes density greatly over a range of temperature. So keeping track of the changing temperatures of the incoming air and the engine in which it is burnt becomes very important. But due to its simplicity of design, the ECT is rarely at fault when problems occur. The engine temperature must be greater than 50°F (10°C) to pass the KOEO Self-Test and greater than 180°F (82°C) to pass the KOER Self-Test. To accomplish this, the engine should be at normal operating temperature...Before you start blaming the engine coolant temperature sensor and replacing it make sure the rest of the coolant system is in good condition. All of the following items will affect the ECT: *Coolant level *Radiator Fan *Water Pump *Water Pump and Fan Belts *Thermostat *Base Timing *Engines general condition *Harness and wire general condition..."
Source: by Ryan M (Fireguy50) at http://fordfuelinjection.com/?p=10
& MORE @
http://fordfuelinjection.com/index.php?p=28
 

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Does it feel underpowered, not accelerating well?

Sounds like a clogged cat. What does the exhaust smell like?
 

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Discussion Starter #11
Checked ect and it checked good started at 7 volts and dropped to around .65 volts at op. Temp. Ran another self test and got an 11 and a 34 checked voltage to evp and it checked at 5 volts. Exhaust smells kinda sour and it feels like it's dragging it's butt
 

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Discussion Starter #14
What is specs on fuel pressures? Mine with engine off and FP grounded is 30. And with engine running is 35 but the pressure bleeds off when I shut the key off it falls to about 15 to 20 psi does that mean my regulator is bad?
 

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What is specs on fuel pressures? Mine with engine off and FP grounded is 30. And with engine running is 35 but the pressure bleeds off when I shut the key off it falls to about 15 to 20 psi does that mean my regulator is bad?

"Normal" fuel pressure for Ford EFI computers is around 39-41 PSI, which will vary with manifold vacuum changes.

A fuel pressure loss of more than 5 psi within 60 seconds after pump shutdown may indicate a bad Fuel Pressure Regulator. Fuel found in the FPR Vacuum Line or Port is also an indicator of a bad Fuel Pressure Regulator.


Normal fuel pressure for all 1989-1999 Ford Trucks, except 4.9 L engine:
- Key on, engine off: 35 to 45 psi
- Engine running: 30 to 45 psi
- Engine running with vacuum hose unplugged from FPR: 5 to 10 psi increase

Normal fuel pressure for all 1989-1999 Ford Trucks with 4.9 L engine:
- Key on, engine off: 50 to 60 psi
- Engine running: 45 to 60 psi
- Engine running with vacuum hose unplugged from FPR: 5 to 10 psi increase



Ford Fuel Injection - Fuel Pressure Regulator

Ford Faulty Fuel Pressure Regulator Symptoms

Fuel Pressure Regulator - Ford Truck
 

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Discussion Starter #17
Well I put a new fuel pressure regulator on....what a pain in the arse....!! Anyway also went ahead and just for the heck of it I went ahead and put new motorcraft plugs in it gapped at .045.... Fixed a vacuum line going to my charcoal canister. Warmed it up and pulled codes and got 11's on both tests.. Ate dinner and them took it for a test drive and NO improvement it still pops and is gutless I noticed the warmer the motor gets the worse it does it. I also have had a ticking coming from the back of the motor that I just can't pinpoint.. Now what do ido do you still think it could be my ICM or maybe my coil breaking down? I checked all vacuum lines and they don't leak... appreciate all the help guys!!!
 

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penis
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If it was your coil it will be doing it while in park/nuetral when you press the gas, I am leaning more towards the ICM as it appears top be failing under load and you have no codes as well.
 

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yo,
Try some simple TFI, Coil, etc tests before buying new parts; and anyy TFI ign parts should be Motorcraft Brand or Wells.

Try this;
Troubleshooting, Overview & Operation; "...Ford calls this electronic ignition the Thick Film Integrated-IV (TFI-IV) ignition system. The TFI module is also known as the Ignition Control Module (ICM) which reports engine position and rpm to the PCM. The PCM then determines the proper spark timing and advance, and returns a reference signal to tell the TFI module to switch the coil, thereby by creating a spark. The PCM used on these vehicles is referred to by Ford as the Electronic Engine Control-IV (EEC-IV) module..." read more
Source: by therangerstation.com @ http://www.therangerstation.com/tech_library/TFI_Diagnostic.html
So far, others incl Steve have validated that this is good for our broncos as well as Rangers and othe Ford TFI equipped trucks.
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As for da "... ticking coming from the back of the motor..."
That could be detonation, so ck Timing
or could be the 2nd Air Sys crossover tube/check valve rusted out or off.

5.8L Secondary Air by Steve
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Crossover Tube for upstream secondary air on V8. by Steve

by Steve


use a mirror and flashlight to inspect the tube and valves
Use a section of garden hose etc to use as a stethoscope to track ping down; have someone apply Parking brake and use a Big Foot on da brake Pedal and have em accel very slowly in gear; would be good to have front bumper against someone else's concrete wall or a guard rail... be aware of fan, belts, pulleys and hot engine.

Timing Adjustment by Ryan M (Fireguy50) at http://fordfuelinjection.com/index.php?p=71
 

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And;
NO CODES Troubleshooting; miesk5 NOTE, The self-test plugs were mounted on the passenger side fender on 1985-86 EFI trucks. Self-Test Output (STO) is the Pin in the Lt gray Connector and Signal Return Ground (SIGRET) is Pin E in black Connector; The engine temperature must be greater than 50°F (10°C) to pass the KOEO Self-Test and greater than 180°F (82°C) to pass the KOER Self-Test. Run it around to heat the engine up and shift thru all gears incl Reverse. then; turn off all accesories/lights, etc. Make sure A/C is off and transmission is in Park (automatic) or Neutral (manual), release clutch. Do Key On Engine Off (KOEO) portion first. For Key On Engine Running (KOER) portion, the engine has to be @ normal operating temp. Look Codes up in my broncolinks.com site using the new Search function.
Source: by Ryan M (Fireguy50) at http://fordfuelinjection.com/index.php?p=44
 
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