Vanning.com logo
Boxdin
Site Navigation


Advertisements
Recent Posts
'88 B250 running problems
by KogonDodge - January 27th 2021 3:37 pm
Van Prices
by Charlie99909 - January 27th 2021 2:53 pm
Sweet Spot
by Sweet_Spot - January 27th 2021 1:02 pm
New guy in north Texas
by Wedgy - January 27th 2021 12:56 pm
Not new... but been away a long time!
by Wedgy - January 27th 2021 12:47 pm
Featured Links
Vanning.Com is a an authorized Amsoil Dealer


Previous Thread
Next Thread
Print Thread
Rate Thread
Page 1 of 2 1 2
'88 B250 running problems
#768693 December 17th 2020 3:20 pm
Joined: Jul 2020
Posts: 10
stranger
OP Online Content
stranger
Joined: Jul 2020
Posts: 10
Hi all, thanks for this awesome site. I have got a real thing for classic vans and love to learn and work on my own 1988 Conversion van 5.2l TBI. I tried to put a picture of the van in my signature and resize it, but that might have gone wrong, I guess I will find out when I post this.

When i bought it, it had been unused for some time. I did a service and replaced plugs, coil, distributor cap. oil, trans fluid, filters. It would surge and stall at idle though from the moment I first started it, very annoying, made it difficult to park for a start. I played with lots of things but what finally did it was when I replaced the throttle body gasket and the O2 sensor. One of those did the job. The gasket was very "welded " on but I couldn't really see how that could cause a bad air leak versus, say a holed vacuum pipe. I checked all the vacuum pipes at the same time, everything seemed fine.

2 yeas later, and this may be unrelated, I am having problems going up hills. No power and overheating. Admittedly I was 5 up, with a lot of load and it was 100 degrees but it got real hot, real quick. I eventually investigated the timing and found it was out, it was about 4 degrees, I changed it to 12. Tried the same hill after and it did get hotter on the gauge, but only by a bit. Generally it feels more peppy and happy.

There was another problem, that occurred during all this and still lingers, is a jerking under load (up hills for example), at freeway speeds. It almost feels like it is changing down. I think it is a misfire under load. After I changed the timing to 12 degrees this went away and it changed through the gears very nicely so I don't think it is anything to do with the transmission. But this problem has come back

However, it is now also doing the unhappy idle thing again, including stalling when I am driving down the road, in drive, but with no gas pedal (downhill). That was pretty worrying. So I am back to trying to figure out what this problem is.

Maybe the gasket/O2 sensor has gone again?
Has 2 years of incorrect timing lunched the plugs?
Something to do with the choke (i am in socal though, so it never gets below 50 degress!)

I've got a new coil and new plugs on their way to try and address the misfire problem.

Any suggestions?
TIA

Re: '88 B250 running problems
KogonDodge #768704 December 18th 2020 8:06 am
Joined: Aug 2005
Posts: 20,877
Likes: 7
N
Supreme Master
Offline
Supreme Master
N
Joined: Aug 2005
Posts: 20,877
Likes: 7
Chrysler TBI of that era are notoriously problematic.

Seriously consider swapping over to a carburetor.


Nate Breece
--------------
1993 Chevy G20
2012 Hyundai Santa Fe
Re: '88 B250 running problems
KogonDodge #768902 December 23rd 2020 3:19 pm
Joined: Apr 2010
Posts: 2,769
Likes: 6
W
veteran
Offline
veteran
W
Joined: Apr 2010
Posts: 2,769
Likes: 6
I often read about how crappy the chrysler TBI system is. I've a 1989 b250, for 20+ years and 100K+ miles now, and just drove it cross country, or I would have responded sooner.

i don;t want to Taunt Murphy, but

The only surging issues I had, was when I had a failing fuel injector, which is about a 2 minute job to replace and a new injector is under 50$. It is pretty easy to see feel and hear the difference in a malfunctioning fuel injector with the air cleaner cover off. can swap the injectors to see if the problem follows the injector or its wiring

I have had issues with the engine computer. The original likely failed because of a wire to transmission overdrive solenoid was shorting to ground. The replacement ECM was damaged about 12 years later, by the weight of the wire bundles of the 14 wire connector hanging on the solder joints of the 14 pins. I removed the potting, reflowed the solder, and no more issues. I also remove the weight of that wire bundle from potentially stressing the circuit board's pins. Turn the Key to On, not start, and gently apply different pressure to the 14 pin connector. if you hear a relay or relays click on and off it is likely that this is now, or will soon be an issue.

Get some Caig DeOxit d5, no other electrical contact cleaner comes remotely close, but they are useful for helping to flush out old crusty dielectric grease, as the Caig is too expensive for this task.

Do ALL the sensor connectors, MAP and TPS. 02 sensor, coolant temp sensor as well as at the ECM. Every connector you can find. open it flush out old dielectric grease with CRC QED and bottle brushes, then Caig Deoxit.

Flush the connectors of old dielectric grease with CRC QED or similar, and some dental style bottle brushes, then use the Caig Deoxit and the same brushes. Some small precision swabs soaked with deOxit afterwards on the pins, will likely turn black and the pins go from grey and dull to gleaming like silver.
https://www.amazon.com/Tamiya-Cotto...mp;psc=1&refRID=326PHGWF1QMFFS6JMPKB


The sensors get sent only 5v and the engine computer sees a returning voltage on these connectors and determines fuel air ratio and spark timing, so highly resistive connections from corrosion on a 32 year old vehicle can have huge effects on driveability, MPG and power. the lower the voltaeg the more affected they are to electrical resistance. Doing all my sensors alone made it feel like I removed 500+ Lbs from the back of my van. Throttle feel/driveability improved dramatically just cleaning the sensor connectors.

Do NOT be one of those people, who opens an electrical connector, sees dielectric grease, and assumes all is fine within and reconnects it I've had di electric grease peel off pins and sockets like 30 year old scotch tape, after removing all the grease which appeared fine and dandy surrounding it.

The engine computer gets its ground, from the intake manifold where the ignition coil attaches. Make sure this is clean and tight. Follow the original battery to engine ground, remove file/wire brush shiny spray with deoxit d5 and retighten. Follow the smaller wires to from battery negative to firewall, behind battery. Same treatment.

It is a good idea to ground the frame to the Engine as well. Best would be the same bolt as the Battery to engine ground, and best if this is a bolt holding the alternator bracket.

The ONLY way I would consider a carburetor swap is if I could not get a new ECM or the parts to repair mine, AND I was not concerned with either fuel economy or having to pass emissions tests.

if driveability conditions happen only with low levels of fuel in the tank, it is likely the fuel pump is on its way out, but do check the connector and the frame ground for the pump at the cross member at the fuel tank. Same CRC QED then Caig Deoxit treatment here. The lower the voltage reaching teh fuel pump the hotter and harder it hat to run to supply the fuel needed, so a shitty electrical connection here can induce premature fuel pump failure. the wiring gauge and the extreme length of it that chrysler used is also pretty inadequate even for the 4 amp load of the fuel pump. I bypassed around 10 feet of it as it actually runs up and over the upper frame rail over the back doors stock. I think the power for the Fuel pump is a green wire with red stripe, 16 or 18 AWG. It gets ground from the nearby cross member. This is where the additional frame to engine ground can be beneficial.

One last thing, is the cabling at teh battery itself. often this grows green or white corrosion, and the owner removes this corrosion and thinks all is well. I am not sure how it is NOT all OK, but I have witnessed on more than one occassion weird electrical issues stemo from battery cables which once had visible corrosion removed. opening up teh wirin insulation shows the corrosion wicked well up the wire stranding, and then sometimes the 6 or 4 sae gauge wire would refuse to pass any current, or cause weird intermittent issues that are easily solved with new battery cables.

Do be aware that many parts store cables, use steel ring terminals.

On a scale of 1 to 100 and copper being 100, steel is about a 4, depending on teh alloy, and steel rusts.

If you need new battery cables:
https://www.genuinedealz.com/collections/custom-cables

The prices are likely less than parts store crap, and he uses professional tools and top quality components and stuff arrives quickly with free shipping.

Parts store cables are SAE gauge, which is 6 to 12% thinner than AWG, american wire gauge, with correspondingly less ampacity.

Re: '88 B250 running problems
KogonDodge #768938 December 24th 2020 10:42 am
Joined: Jun 2010
Posts: 1,075
N
old hand
Offline
old hand
N
Joined: Jun 2010
Posts: 1,075
Out of curiosity do you have a ballast resistor on the firewall? Have you checked it?


Nicole
1988 Dodge B250 5.9l 360 Ram CamperVan / 727 Tranny / Rochester Quadrajet Carb
www.nikothenomad.blogspot.com
Re: '88 B250 running problems
KogonDodge #769342 January 04th 2021 2:06 pm
Joined: Jul 2020
Posts: 10
stranger
OP Online Content
stranger
Joined: Jul 2020
Posts: 10
Hi Nicole, thank you for your reply, sorry to not respond sooner, I only just checked back.

I have changed the coil and spark plugs over the holidays; did not make a difference. The coil said it was for a ballasted system so I assume there is a ballast resistor. I will check.

I replaced the fuel filter, fuel pump and all fuel hoses on this van since I bought it. I think I replaced the fuel pressure regulator too. All in the name of either good practice, or throwing parts at this problem.

I take your point on checking all the electrical connections and I will do that first chance I get. One thing with this van is is seems to have sat for a solid 10 years before I bought it so electrical issues would be a strong possibility especially as this seems to be intermittent and less noticeable when the engine is at operating temperature. I have some of that deoxit stuff already.

I am also going to hunt down a possible vacuum leak as the surging suggests unmetered air getting in and the system dumping fuel to correct the fuel trim when the o2 sensor sees the results. This problem with the surging and stalling at idle happened when I first bought it and one of eitherTB base gasket replacement and O2 sensor replacement solved it. I'm going to re torque down that throttle body. I checked every possible vacuum line at that timeand they all seemed fine.

Re: '88 B250 running problems
KogonDodge #769353 January 05th 2021 12:31 pm
Joined: Jun 2010
Posts: 1,075
N
old hand
Offline
old hand
N
Joined: Jun 2010
Posts: 1,075
Hi Kogon.... No worries. I sent you a private message. Good luck with the fix!


Nicole
1988 Dodge B250 5.9l 360 Ram CamperVan / 727 Tranny / Rochester Quadrajet Carb
www.nikothenomad.blogspot.com
Re: '88 B250 running problems
KogonDodge #769546 January 10th 2021 9:46 pm
Joined: Mar 2007
Posts: 4,403
Likes: 2
pooh-bah
Offline
pooh-bah
Joined: Mar 2007
Posts: 4,403
Likes: 2
Due to the amount of time which has gone by, and the age of the components, it might be worth inspecting the vacuum hoses around any evaporative control charcoal canisters. They can create massive vacuum leaks. If there's a master canister, the internal control diaphragm may rupture, leading to a nasty hidden vacuum leak. That can be tested with a handheld vacuum pump.

If you have the three barb fuel filter, make sure your return line isn't obstructed. That could lead to vapor lock type issues.

Have you tried spraying carb cleaner around the throttle body exterior while the engine is running to look for any changes in RPM which could indicate a leak?

Is your air cleaners heat riser tube still intact? Is your choke kick solenoid opening the choke plate firmly so it can't drift or flutter?

Does your engine have a crankcase breather air inlet filter on top of the passenger side valve cover? If those clog up a variety of peculiar symptoms can result. PCV malfunction type issues, including idle issues and varnish buildup being the most common. Air should pass through them with very little resistance. And believe it or not, they're an oil bath air cleaner! They require periodic servicing by pouring a few spoonfuls of light oil in them to wet the filter media, like you'd do on a K&N air filter.

Double check your exhaust Y-pipes and joints for any pinhole leaks. If you have the air injection system or an aspirator valve, the little thin metal pipes which bolt into the rear of the exhaust manifolds can develop disruptive leaks too.

Have you ever verified that the throttle kick down adjustment is correct? It seems to almost always be wrong when someone first tries to get the bugs out of a previously owned van. It is responsible for modulating some of the fluid line pressure inside the transmission. It can cause issues at idle if it's way off, (throws the idle rpms off due to the load of the pump) cause shifts to occur incorrectly, particularly late or early, or even lead to alarming bucking. If you need the adjustment procedure let us know; several of us have feild service manuals containing the procedure.

Last edited by Ram4ever; January 10th 2021 10:07 pm. Reason: more details

-It's been such a LONG TIME... BlueShift>> 1981 Dodge Ram B250 Custom Sportsman Maxi Van


[Linked Image]

It's what you learn after you know it all, that counts...

Are you living to work, or working to live?

[Linked Image]

Learning from my own mistakes is good, learning from yours would be much better! [Linked Image]
Re: '88 B250 running problems
KogonDodge #769600 January 12th 2021 1:51 pm
Joined: Jul 2020
Posts: 10
stranger
OP Online Content
stranger
Joined: Jul 2020
Posts: 10
Hi Ram4ever, thank you for taking the time to make some suggestions. I'm not able to work on the van until this weekend but I will go through your points. Some of them are already "yes" and "does not apply" but I will go through them.

Regarding your last suggestion, I'd be grateful to see that procedure. I have a alldatadiy subscription but i can't find that procedure searching under "throttle kick down"?

I have changed the trans fluid and adjusted the bands, twice, so I know they are in order, but I don't think that's what you mean?

Re: '88 B250 running problems
KogonDodge #769608 January 12th 2021 7:18 pm
Joined: Jul 2020
Posts: 10
stranger
OP Online Content
stranger
Joined: Jul 2020
Posts: 10
@Ram4ever

Does this sound like the right thing?

On all models, raise and support vehicle, then loosen adjustable swivel lock screw, Figs. 12 through 14. Ensure swivel slides freely on throttle rod so that return spring action is not restricted. If necessary, disassemble and clean or repair parts to assure free action.
Hold transmission throttle lever firmly forward against its internal stop and torque swivel lock screw to specifications.
Lower vehicle and test linkage operation by moving throttle rod rearward and slowly releasing it making certain that it returns fully.

Re: '88 B250 running problems
KogonDodge #769624 January 13th 2021 1:50 am
Joined: Apr 2010
Posts: 2,769
Likes: 6
W
veteran
Offline
veteran
W
Joined: Apr 2010
Posts: 2,769
Likes: 6
My 89 TBI has a throttle rod between throttle body and A-500 overdrive transmission.

On the drivers side of the TB there is a mechanism to let the TX know the degree of throttle input. There is some sliding of this linkage at the throttle body. The throttle pushes the linkage back, and the TX allows it to return as it wants, with some spring assist.

If it does not slide easily, the TX will be confused.

I had this linkage fall off. It would shift quickly into third gear, nearly instantly when accelerating.
No stalling.

At the TX there is a half inch bolt.

When adjusted as the factory or haynes manual stated, I though it shifted way too late and too harshly, as I would drive. It felt fine if I was accelerating hard, everywhere and did not give a flyingFVck about fuel economy. But I dont so I dismissed the factory service manual and the Haynes

I drove around with a 1/2 inch wrench and would stop and adjust it 1/16" increments until it shifted where I wanted it to shift from first to second and second to third.

I have about 80k miles on the rebuilt TX with it adjusted to MY desires, as to where it shifts.

With no Running boards lifting the vehicle is not needed to access this adjustment point.

Ram4ever, I deleted my FB account, so No more messenger either.

1 member likes this: Ram4ever
Page 1 of 2 1 2

Moderated by  Astro, Ram4ever 

Link Copied to Clipboard
Donate


discovery
Who's Online Now
0 members (), 7 guests, and 7 robots.
Key: Admin, Global Mod, Mod
Newest Members
oregoncoast, Hellisia, ajm5034, dat521, Moonlightsailor
11784 Registered Users
Top Posters (30 Days)
SDMickey 170
frscke1 76
NateB 26
Lee7673 24
Forum Statistics
Forums68
Topics38,539
Posts540,112
Members11,784
Most Online177
May 8th, 2013

Powered by UBB.threads™ PHP Forum Software 7.7.4