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well this sucks...prioritize me

3K views 29 replies 10 participants last post by  88rustsurvivor 
#1 ·
GO TO LAST THREAD!!! ok first of 1988 EB 302HO AOD. this EFI is makin me mad!!! i have a continous lean bank1, bad or semi-bad O2 sensor, and i just replaced the TFI twice; now my timming is bouncing about a 1/2 of a degree. thats just electronic stuff. now the thermostat isnt comming on till the temp hits H then it works fine, broken EGR/smog pump tube, bad smog pump. help me get this stuff prioritized so i can get this thing fixed before more bad things happen. i know that the thermostat going is probrobly causing the TFI module to go. so thats gunna b fixed tommmorrow. but from there, How much trouble is that EGR/smog pump line going to be for me. and only recently in 4x4 when shifted into gear the engine seems like its "tripping over itself" and almost stalls.

extra info, timing:16-17BTDC, 3G alt, electric fan with independant module,
 
#3 ·
your timing will move all over the place if the spout connector is plugged in.

as for the lean bank, could be the O2 sensor, exhaust leak before the sensor or a intake leak.

as for the tstat is sounds like your looking @ the stock POS guage. This could be a bad sender, loose wire, or the guage is dead.

check all your grounds, including your battery cables.
 
#13 ·
have you even looked into any of this other than throwing another TFI at the thing?

A carb on it is not the answer. :twak



btw, you should check the pickup in the dizzy. I bet there is something wrong in leading you to think the TFI's are dead all the fricken time.
 
#4 ·
well i just replced the TFI module earlier today and i did it in the dark and i might have forgot to take off the spout, makes sense before it was rock solid. the exhuast leak is the tube behind the first cat but its broken up behind the engine. heres another problemm i forgot, sometimes the alternator doesnt voltage up all the way just to around 12volts but its still working, voltage restores to the 12volts and all when i turn stuff on. both the 3G and the old 2G did this so im guessing wutever is in the computer that doing this
 
#18 ·
That's not good. Check your ground cables, battery cables and connections.
When I did my 3G swap all the cables, ends and connections were replaced.
stock cables were upgraded to 2G welding cables with copper ends soldered
on. Where ground cables were attached frame was sanded clean. HD ground straps installed between engine and frame.
Die electric grease all connections also.
It charges at 14.5 at first doesn't drop any lower that 14V no matter what I have on.
Dave
 
#20 ·
well i just replced the TFI module earlier today and i did it in the dark and i might have forgot to take off the spout, makes sense before it was rock solid.
let this be a lesson!! always remember to take off that darn SPOUT connector. i spend about 5 hrs going through relays and alldata when in the end i checked my timing(the right way) and found it was running 5*BTDC, reset to 20*BTDC(5.0HO settings) and now its running like its supposed to.
 
#5 ·
well once again this sucks!!! my truck died and wont start AGAIN. this crap seems to happen when i let it idle for anytime more than 3min, when i put it in gear it just dies and wont start unless i replace the TFI.
 
#7 ·
not with fords EEC-IV system, it takes forever till the computer even realizes whats wrong, like my exhuast leak after my truck is driven about 30miles it will give me a code about the EGR valve and lean bank. Fortunately i have a carbureted 302 layin in my yard with all the accessories that all i need is gaskets and a new fuel system and i can swap it in a day. I do believe that my computer has something f'd up with it or even the PCM
 
#11 ·
ya i know my junk yard is really cheap if you can find a supercharger its only 50 bucks, turbos are 25. anyway i think ill throw in a 351 computer since my engine has that firing order 302HO, unlike was the current ECM tells me thats in there 302 with the 1-5-2 order

EDIT: it started for me, im realizing that before all of this the engine idle sounded nice and calm like it should. now it sounds like a 60's mustang or sumthing.
 
#15 ·
you said you have a charging problem? is it actually over charging? I guess there is the possibility of frying parts from over charging.
 
#16 ·
its not over chargin it just doesnt go up to the 15 volts it usually does it just stays at 12, but the alt is working. i have discovered today that the engine is running just rich enough to idle but once load is on it(in drive or reverse) it stumbles on itself and stalls. about 10 minutes later i can start it with that lovely gassy smell.ive looked threw alldata and added a ground to the body incase there was an issue with that.from there i idled it while unhooking relays and such hoping that i can find the one not working, no luck.
 
#17 ·
man that sucks i know how you feel tho! good luck!
 
#19 ·
little update so far on a systems check. my fuel pump relay, and both fuel pumps are operating normal and at the proper pressures. i pulled spark plugs, they have some soot on them but it comes right off by touchin it. then i started it with a plug out, plenty of compression and powerful spark, but i didnt notice any fuel smell?? im considering checking the injectors next. could a intake gasket be doing this??? i have little to no torque within the first 10 minutes of driving.
 
#22 ·
Thanks, for getting that comment in there, I started to think I did something wrong in setting mine. Mine is at 13 btdc because I did the MSD upgrade and according to Steve83 and a few others that's what was recommended.
 
#23 ·
wow you guys have regular 302's though. settings are supposed to be 10* this has an HO set to 20*. i did do the "magic" 13.5* setting for awhile with terrible gas mileage and little lowend torque. now with it set at 20* i get the most ive seen with 160miles to a half tank, driving it like i stole it and at least 30 miles with the hubs locked or in 4x4. i still am running rich like crazy but its alot worse anywhere near 10*.
 
#25 ·
302 HO in a Bronco? E7 heads, roller cam, and 351 firing order? Was it transplanted from a Mustang or Mark VII? Even if tis indeed an HO engine, timing is still 10* BTDC, matter of fact I ain't never heard of any stock engine that runs 20* initial timing, Ford or Chevy. You're running rich cause that messed up O2 sensor you got reads false and keeps telling the ECM to hang the injectors open longer, which it promptly does. The engine should run fine at 10* BTDC, so those 20* you got there, are you sure tis really 20? You're supposed to set timing with the engine fully warmed up (so low idle rpms and no centrifugal advance), SPOUT connector pulled (so no electronic spark advance either, but you already know that) - if you were idling at like 1000rpms you got the centrifugal already engaging so those 20 degrees ain't true initial. Also, what timing light did you use, a simple one or a dial-back type? If you got a dial-back you may have had a blonde moment and set it wrong, or you were looking at the wrong markings on the balancer... Bottom line is, something ain't right with all that, I know folks who run 20 or so initial timing, but tis on carbed engines, with the dizzy recurved and centrifugal advance restricted to proper levels (16* for 20* initial, making total of 36), and also no vacuum advance at all...
 
#24 ·
heres the finisher on this one.
1.new TPS
2. new fuel pressure regulator
3. reset curb idle according to alldata procedure
4. seafoam
5.clean (or replace) plugs
idles like a dream back to 180mi for half a tank and no more stalling!!!!!!!!!
 
#26 ·
ok ive been looking at this timing thing, my computer only advances the timing by 10* instead of by 20* like everyone else's. i used a MAC digital timing light with rpm settings and all that stuff. yes I removed the SPOUT. the o2 sensor has been replaced-i forgot to add-. unless u can give me that i have a 351 in this thing its gotta b a 302HO. first off i have the old intake without the engine size, i havent owned it for its first 176,000 miles. my firing order goes 1,3,7 instead of 1,5,4 and the block has 302 on it. I also used the rpm display on the timing light to set the curb idle properly according to ALLDATA. and it worked the BKO works fine now given it fluxuates about 50rpms at stop lights at 850rpm.
 
#27 ·
Man, the Bronco ain't even a work truck - Ford didn't care enough to install a SEFI on these things, what makes you think they put in an HO engine? Being an '88 you should have the HO heads, I give you that, but no way you got a roller cam and forged pistons, not from the factory at least. The firing order is based on the camshaft, so if one of the previous owners installed an HO or a 351 cam in it that will require the firing order to be changed... with a SEFI system you'd also have to re-pin the injector harness, but you got batch-fire so that ain't no issue for you. With the fullsize cars we do all sorts of HO swaps, from just intakes to full HO swaps and everything in-between - I know of a guy who runs a ported non-HO intake and EGR spacer on an otherwise HO engine cause it gives him more air speed and better fuel economy and somewhat more low-end torque. Like I said, unless your 302 came from a Mustang or a Mark VII LSC you ain't got no HO engine, just an HO/351 cam.

Now, about timing, don't even try to measure what the ECM is doing with a timing light - how much advance it pulls depends on many things you really have no control over, such as the ambient air temperature for instance, the quality of gas, and so on. If you throw the light on it while idling fully warmed up you only see what tis doing at that particular moment for those particular conditions, bet if you somehow got a full tank of summer-blend gasoline now and ran off that you'd be seeing different things. So just cause most folks say their ECMs pull 20 degrees of advance at idle don't mean yours will do the same at the exact moment you decided to take measurements, and you having that cam in there throws things off even more.

By the way, I ain't bashing on ya, I'm just trying to explain some misunderstandings. However, something that just came to me - you said your truck runs beautifully at 20* initial, and since that clearly ain't the stock cam, what if during the install someone messed it up, and ended up retarding it? Most timing sets allow you move the cam 8 degrees in either way, so if the installer wasn't paying attention they could have ended up with 8 degrees in the wrong direction, which certainly affects idle and low end.
 
#28 ·
OK now thats it been a YEAR since this crap was going on. MLSC I dont know about the pistons and cam etc. etc. I'm going to doubt that. ANY WAY now its doing this again!! BLARH, now I have a manual transmission and updated wiring harness. NO CODES. OK for about the last month I noticed a slight jerk or surge while lightly on the gas at highway speeds. the other day going off-road I went through a nice puddle, drove 500ft and the truck died. It will start for about 2 seconds then runs what sounds like on every other cylinder with me tapping the gas. then no matter what it dies. I put a fuel filter in it about 6 hours later and drove it home about 15 miles, ran this morning, then did this again in the middle of the day just driving it. when the truck is moving it feels like I took my foot of the gas(decelerating) now matter what I do. when its cranking the motor isnt even trying to catch after it stalls. the distributer is dry and I WD-40'd the electrical connections. fuel pumps and all relays are working. this is very intermittent and happens out of the blue right now. timing is set and there is spark and the coil is good, the tachometer still shows RPM when the truck is stalled at speed. searched a bit but the threads didnt have an answer or was an answer that I dont have a problem with.
 
#30 ·
today it hasnt happened, Im looking at pinpiont charts from the ECM. there is a TSB about the older ECMs may act up just like this. I just remebered that months ago it did this for 5 days straight at the exact same spot on the road goin to work. I was like I let off the gas for about 20 feet then run fine and dandy. the hall effect sensor and TFI are on my list of the few things that could do this. Does anybody know if the fuel accumulator can clog?
 
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