This is really ticking me off!! This has been going on for a while now and I can't get it fixed. 1990 Bronco with 5.8 EFI. Cold starts (funny I'm using the word start) are extremely difficult. She sputters and dies unless I have the pedal to the floor - then when it does start, I get black smoke and hard to keep it running unless I constantly adjust gas pedal. It is almost like it is firing on two or three cylinders then after a minute or two it levels out and idles like it should. But if I apply a small amount of throttle it hesitates and almost dies. I pulled the codes and got:

565 Canister purge solenoid
327 EGR valve position circuit below normal voltage
334 EGR closed valve voltage high

I replaced the EGR valve and the sensor that mounts on top of it. Cleared codes and tried again. IT STILL STARTS LIKE CRAP! Sputtering and spitting black smoke.

I drive it for about 20 minutes - the hesitation at low idle is still there - but other than that she runs fine at high speeds and acceleration is strong.

I pull the codes again and get:

328 EGR closed valve voltage lower than expected
116 Eng temp sensor too low/high

Over the last two months I have replaced the injectors, emissions tubing from rear of eng to air pump, O2 sensor,EGR valve, spark plugs, wires, verified the timing at -10 BTDC. I,m running out of options and $$!

Not sure why the temp sensor shows as a fault code. The truck does not overheat or run below temp. Could this be causing all this mayhem?
ANYONE HAVE ANY IDEAS?

 

Did you take the battery off when you changed the sensors? If you didn't the ECU will still be working on the old parameters given from the old sensors. Disco the battery for 30 mins then reconnect, start it and run it for 30 mins over mixed terrain for the ecu to relearn the sensor parameters. See if that helps.

Also double check the plug wires ain't crossed.

Probably need GreyStreak92 to answer this but I think he's on holiday at the moment.

Simon

 

Also check the IAC valve ain't jammed shut - its on the side of the TB.

 

I have a Dodge p.o.s. and one of the many times it had a problem was a m.a.p. sensor went out and dumped more fuel down it and alot of carbon built up and it was doing the same thing your talking about, took it to a shop and paid $600.00 to find out all they did was pour an injection cleaner down it called B-G 28.Most of what I paid them was to track the problem down,then when they were done it ended up flushing all the carbon down onto the O,2 sensor and here we go again,same problem.See if you are having too much fuel going down it and if so why.

 

Yeah you need to check your pressure on the fuel line. Sounds like yours may be high if you've replaced the injectors already.

 

Black smoke is generally an indication of too much fuel or not enough air. Check all the easy stuff first - all of the sensor electrical connectors (unplug them and plug them back in), clean air filter, etc. Make sure and check the fuel pressure. The regulator should keep it at about 39psi. I had a regulator go bad on my '94 5.8L and it was blowing black smoke and getting 11mpg. Checked the fuel pressure and it was about 85psi. New regulator - problem solved. Also make sure the gas tank is venting properly. This is done through the charcoal canister, but you can just disconnect the vent line at the canister and vent to atmosphere to test it (or you could just remove the gas cap). This would make sure you are not building pressure inside the fuel tank.

Hope this helps.

 

Thanks for the info and trying to help out with this.

I disconnected the battery for about 1 hour and ran the truck for about 45 minutes. The starting problem is still there. While driving, she ran pretty good for a while but then the Check eng light came on and she started sputtering while going up hill at about 60mph. The check eng light stayed on for about 5 minutes then went off. When I got back home I re-checked the codes:

328
565
327
328
334

All of these are pointing to the EGR valve which I already replaced!

I do not know how to check the fuel pressure, I see the valve on the fuel rail. Will a regular tire pressure gauge work? Also, WTF is this EGR valve doing. I know why it is there and what its function is supposed to be, but this is getting a little crazy. Can I block it off and unplug the sensor? I'm not worried about smog, I just had the thing smogged a week ago with all these problems and it passed.

The IAC was checked about two weeks ago and it looked clear. I sprayed it out with carb cleaner and re-installed. Didn't fix anything.

 

Tire gage won't work. Most auto parts stores will sell a fuel pressure test gage for around $20. Attach it when the engine is not running. The fuel rail will or should maintain pressure with the engine off, but without the pump running its not a big deal.

The EGR is for smog purposes and is mainly used during cruise. Without it you might possibly have some engine ping as a result of an advanced timing curve the ECM uses. You can read up on EGR on the internet.

 

116 Eng temp sensor too low/high. this is not the temp gauge or light.this sensor tells the comp what temp the motor is at, I'v seen them fail with exactly what you are having problems with

 

when you set timing you removed spout connector correct. also like bodyman stated the eng temp sensor needs replaced. this is located in the middle of lower intake driver side. replace this. also check all vacum lines running from the evp solenoid to the egr and the cansiter. the hardlines crack so you might just replace with basic rubber vac lines. double check your firing order and definatly check the fuel pressure. check your oil an make sure it doesnt smell like gas if it does its definatly your FPR

 

Another quick check would be to pull the vacum line from the fuel pressure regulator. If fuel is running like no tommorrow replace the regulator. My 95 acted just as yours and well it quite doing so now.Egr codes were thrown because of excessive fuel.

 

Today I replaced the temp sensor and fuel pressure regulator. Cleared codes and went for a drive. She started crappy and ran pretty crappy for a while. Cleared up a little towards the end. Ran codes again and got:

328
334
337

All EGR codes. Not sure what to do about this since the EGR and sensor are both new. I'll try and put the old ones back on once it cools off.

 

have you check all your vacum lines? and are you sure you set the timing properly?

 

Checked and re-checked all vac lines and verified the timing about 5 times in the last 2 months. Timing is set at -10.

I just went out and started the eng. She fired right up and ran good. No black smoke or sputtering. Idled at about 1300 for a while then dropped down to 600-700.

Think the starting problem is fixed

I can live w/EGR problem until I get the sensor from fordfuelinjection.com that tricks the ECM into thinking its closed.
Hopefully that fixes everything!

 

keep us posted.