Missing and Backfire

[JBronco]

Hello Fellas I got an 88 351 Bronco. To start this story about 2 months ago my bronco just wouldn't start one morning, prior to that morning it was idling a little rough and very rarely it would miss a little when I would accelerate but it was very minor and almost unnoticeable and it had been that way for about a year with it never getting worse. Since it wouldn't start I have changed the plugs, wires, distributor and cap, fuel tank (mine had a small leak), in tank fuel pump, fuel filter, and ERG valve (erg was totally clogged and seized up). Today after completing all that I got some new gas and tried to fire it up. Oh I should have mentioned when it initially wouldn't start that it would just turn over and over strong but it would not start. So when I went to start it, it took a long time but finally it fired up. Once it was idling it was a rough idle and when I would give it throttle it would be very rough building RPMs and if i went over 2500 RPMs it would get real rough and start to backfire and if i held the throttle it will die out backfiring all the way till it shuts off. When I go to start it again it still takes several seconds of turning over before it finally starts. Well that is my problem /emoticons/[email protected] 2x" width="20" height="20" /> I hope I have given enough info for a more savy bronco mech to maybe give me some ideas on what to do next, a buddy of mine said maybe injectors but I hope that is not the case as I don't have the money to do those at the time. So any advice is appreciated. Thanks

 

[chase8266]

did you change the O2 sensor?and with the ecm do you have any engine codes lighting up,im going to assume you have the plug wires right and send you over to this web site which makes it easy to understand the sensors and what could be wrong with your truck.oh your truck might have a spout connector for the electronic controlled distributer if its bad you will get no timming advance,if you have vacumm advance you wont have this.http://fordfuelinjection.com

if you dont get the right answers shoot me an email ill try to help when i [email protected]

 

[JBronco]

Ok so far I have checked the plug wires(they are on the right plug) I have only one vacuum line not connected and it is the small pink one but it has not been connected for 6 years. I am wondering if it could be the external fuel pump, if anyone can give me some insight to know if that pump is bad it would be great before i go waste the money to buy one, would my truck even run if that pump was bad? As far as codes go I do not have a check engine light on or a way to read the codes. The part that I think is odd is to start the truck you have to hold the key for a long time 20 seconds sometimes for it to start. Then it starts and acts just like I said in my earlier post. LOL sorry for thinking while I type really I just wanted some advice if I should try to replace that external fuel pump or not and FYI the external pump does charge when I turn the key so it is not totally dead but maybe not working totaly. Thanks for the help

 

[chase8266]

go to that web site and learn how to pull the codes,my brother has the same yr truck in an f350 model with a 351 says their is 3 fuel pumps on his 1 in each gas tank and 1 external,did you change O2 sensor and is your spout connector ok,if you have a bad spout connector there will be no timming advance.p/s plug vaccum line if you havnt done so already,fuel pressure tester rentable at autozone

 

[JBronco]

I found where the spout connector would be but on my truck it just has a plastic plug in the end that would connect. I know for a fact my O2 sensor is shot but it has been that way for a long time and the truck ran fine without it, I do not want to replace it because i will need the money to fix the main problem. I am looking into how to read the codes but it all looks like Japanese to me so ill work on figuring that out. Do you know if that external pump could cause these kind of issues? It is the only thing along the fuel lines I haven't replaced save the injectors. Thanks for you help it is appreciated.

 

[chase8266]

do the injectors last if needed,read up on the sensors on your truck,map sensor could cause this,your initial timming will be 10 deg.advance when you hook a timming light up to check and you dont disconnect the spout connector it jump up around 20 to 22 deg,this will tell you if this is ok,not to long ago my map sensor gave me a rough idle and shifting probs on my truck.whats wrong with the O2 sensor?

 

[chase8266]

long time 20 seconds sometimes for it to start.

Is that 20 seconds before it turns over or 20 seconds before it actually runs?

 

[Seabronc]

Backfiring is normally connected with timing. Removing the SPOUT connector disconnects the distributor from the computer control. If it still does it then, it is possible that the distributor hold down bolt is loose allowing it to get out of position or you have internal problems like a worn timing chain..

Good luck,

>-

 

[BroncoJoe19]

You stated earlier that you replaced your distributor. You need to set your timing. When you do so, you MUST pull the SPOUT connector or you will set it incorrecty.

Once you have set your timing, then you should reconnect your SPOUT connector.

 

[JBronco]

Ok i looked up the spout connector in my book and where it shows it would be (right where the Distributor goes into block) there is a cable connection that has nothing to plug into and has a plastic plug inside the connection as if it came from the factory that way. The timing chain is new had it put in at the local garage a few months ago and timing was set then and it ran good after that. One thing of note it is getting harder and harder to start sometimes it takes me a min to get it to start it just turns and turns so would that also be a timing issue? It seems now the main issue is that it just wont start and on the rare case it will it has the rough idle and acceleration with some backfiring. I would like to focus on the not starting part, could that be a timing issue?

 

[Seabronc]

Ok i looked up the spout connector in my book and where it shows it would be (right where the Distributor goes into block) there is a cable connection that has nothing to plug into and has a plastic plug inside the connection as if it came from the factory that way. The timing chain is new had it put in at the local garage a few months ago and timing was set then and it ran good after that. One thing of note it is getting harder and harder to start sometimes it takes me a min to get it to start it just turns and turns so would that also be a timing issue? It seems now the main issue is that it just wont start and on the rare case it will it has the rough idle and acceleration with some backfiring. I would like to focus on the not starting part, could that be a timing issue?

Yes that does sound like timing.I could write all this myself, but Ryan a FFI has a great site and tons of info already on line. No matter where the SPOUT connector is, remove the factory plug, that disables the SPOUT signal from the distributor and then check the timing setting. See this article http://fordfuelinjection.com/?p=71

Good luck,

>-

 

[JBronco]

Hey thanks alot for the web info I think it is going to help me, but it still is a little confusing to me because I have never messed with timing in any way. First the spout connector there is nothing that looks like the picture on the website. Now on the side of my distributor mounted below the top along the shaft is a large cable connection and about 2 inches down those wires there is a separate connection that branches off it is much smaller that the connection that does into dist shaft, and that is the one with the plastic plug in it, could this be my spout connection if it is it is not connected to anything it is just hanging there with the plug in the connection. Also I know that TDC is when the number 1 piston is at top of cylinder but I do not know hot to make sure it is or if it needs to be at TDC. Basically all i know about timing is to loosen the lock bold where the dist goes into engine and twist the dist so I have been trying to just twist the dist without doing anything else to see if i could get a better result but it only made the truck harder to start, I did this yesterday before all of your posts. By twisting the dist could I have screwed it up more? I finally think im finding the problem but the info is to much for a newb. I dont know what exactly I need to do all the TDC spout connector 10%advance those things dont mean anything to me, i thought setting the timing was twisting dist till the truck starts and runs smooth but I was wrong so really what I need is some VERY basic and well explained steps on how to set or check my timing.

 

[chase8266]

did these problems get worse after the tune up?please double check your spark plug wires and the order they go,make sure you have number 1 on the distributer cap,and then number 1 on the engine,

351 1-3-7-2-6-5-4-8

Cylinder numbering

The table below covers the positions and numbering for all cylinders on a windsor motor. Generally, it can be summarised as follows: When looking into the engine bay the number one cylinder should be on your left hand side (left bank) at the front of the engine. The number eight cylinder is on the rear right (right bank) up against the firewall.

Firewall

4 8

3 7

2 6

1 5

Front bumper

if you are not sure of number one on cap let us know

 

[JBronco]

Yep the plugs and wires are going to the right spot on the cap, Now I just need to figure out how to do this timing as I said before I am totally lost

 

[chase8266]

did these problems get worse after the tune up?

9 times out of 10 you can trace the problem back to what you did or replaced,learn how to set timming on u-tube,

but do you have a timming light?I dont think thats your problem.

do you know which way your distributer rotates,clockwise or counter clockwise

the spout plug actually connects those 2 wires together,so if there is a break in 1 of those two wires no timming advance will take place

along with some of the other sensors i mentioned their is a TFI module for the distributer that can also go bad

is it backfiring thru the intake or the exhaust?

can you take pics and post them?its hard to figure this out without being there

if all this didnt start after the tune up it will be a process of elimination

 

[Seabronc]

If you have been messing with the distributor position, then you probably made the problem worse. Assuming that the plug wires are on the correct plugs and distributor positions you need to do the basic timing. Ryan's information starts you off like you have pulled the distributor and since you haven't, I hope, you can skip the TDC concern and move on the the rest of the procedure. If you really don't know what you are doing, I would suggest that you find someone that does. I didn't notice where you are located, but there may be someone on the forum that is close to you and can help with on site assistance.

Good luck,

>-

 

[ctryboysurvivor]

ok some basic how to timing, unplug all spark plugs be sure to number them.step1 pull # 1 spark plug . put finger over hole . have someone bump eng over should start filling pressure check timing on harmonic balancer should be close to 0 if not repeat step1 untill on compression stoke tdc.ensure timing at 0 , was on compression stroke,and piston is at the top.now step 2 pull distr. cap were rotor is pointing mark with pin put cap back on and see if mark lines up with #1 post on cap.if all is well it may be another prob.ie bad lobe on cam or poor ign.if durrin step 1 u can not get time lined up at tdc on compression stroke u my have jumped timing.if u are less than 4 degrees or so off just loosen distr bolt and turn distr till #1 post on cap is lined up with mark u made . if #1 post is way off u my have to pull distr and restab it.hope this was a help and good luck.